diff --git a/apache2/Makefile.am b/apache2/Makefile.am
index 2bbc887c..e58e1f54 100644
--- a/apache2/Makefile.am
+++ b/apache2/Makefile.am
@@ -38,7 +38,8 @@ mod_security2_la_CFLAGS = @APR_CFLAGS@ \
     @LIBXML2_CFLAGS@ \
     @LUA_CFLAGS@ \
     @MODSEC_EXTRA_CFLAGS@ \
-    @PCRE_CFLAGS@ 
+    @PCRE_CFLAGS@ \
+    @YAJL_CFLAGS@
 
 
 mod_security2_la_CPPFLAGS = @APR_CPPFLAGS@ \
@@ -49,7 +50,8 @@ mod_security2_la_LIBADD = @APR_LDADD@ \
     @APU_LDADD@ \
     @LIBXML2_LDADD@ \
     @LUA_LDADD@ \
-    @PCRE_LDADD@
+    @PCRE_LDADD@ \
+    @YAJL_LDADD@
 
 if AIX
 mod_security2_la_LDFLAGS = -module -avoid-version \
@@ -58,7 +60,8 @@ mod_security2_la_LDFLAGS = -module -avoid-version \
     @APXS_LDFLAGS@ \
     @LIBXML2_LDFLAGS@ \
     @LUA_LDFLAGS@ \
-    @PCRE_LDFLAGS@
+    @PCRE_LDFLAGS@ \
+    @YAJL_LDFLAGS@
 endif
 
 if HPUX
@@ -68,7 +71,8 @@ mod_security2_la_LDFLAGS = -module -avoid-version \
     @APXS_LDFLAGS@ \
     @LIBXML2_LDFLAGS@ \
     @LUA_LDFLAGS@ \
-    @PCRE_LDFLAGS@
+    @PCRE_LDFLAGS@ \
+    @YAJL_LDFLAGS@
 endif
 
 if MACOSX
@@ -78,7 +82,8 @@ mod_security2_la_LDFLAGS = -module -avoid-version \
     @APXS_LDFLAGS@ \
     @LIBXML2_LDFLAGS@ \
     @LUA_LDFLAGS@ \
-    @PCRE_LDFLAGS@
+    @PCRE_LDFLAGS@ \
+    @YAJL_LDFLAGS@
 endif
 
 if SOLARIS
@@ -88,7 +93,8 @@ mod_security2_la_LDFLAGS = -module -avoid-version \
     @APXS_LDFLAGS@ \
     @LIBXML2_LDFLAGS@ \
     @LUA_LDFLAGS@ \
-    @PCRE_LDFLAGS@
+    @PCRE_LDFLAGS@ \
+    @YAJL_LDFLAGS@
 endif
 
 if LINUX
@@ -98,7 +104,8 @@ mod_security2_la_LDFLAGS = -no-undefined -module -avoid-version -R @PCRE_LD_PATH
     @APXS_LDFLAGS@ \
     @LIBXML2_LDFLAGS@ \
     @LUA_LDFLAGS@ \
-    @PCRE_LDFLAGS@
+    @PCRE_LDFLAGS@ \
+    @YAJL_LDFLAGS@
 endif
 
 if FREEBSD
@@ -108,7 +115,8 @@ mod_security2_la_LDFLAGS = -no-undefined -module -avoid-version \
     @APXS_LDFLAGS@ \
     @LIBXML2_LDFLAGS@ \
     @LUA_LDFLAGS@ \
-    @PCRE_LDFLAGS@
+    @PCRE_LDFLAGS@ \
+    @YAJL_LDFLAGS@
 endif
 
 if OPENBSD
@@ -118,7 +126,8 @@ mod_security2_la_LDFLAGS = -no-undefined -module -avoid-version \
     @APXS_LDFLAGS@ \
     @LIBXML2_LDFLAGS@ \
     @LUA_LDFLAGS@ \
-    @PCRE_LDFLAGS@
+    @PCRE_LDFLAGS@ \
+    @YAJL_LDFLAGS@
 endif
 
 if NETBSD
@@ -128,7 +137,8 @@ mod_security2_la_LDFLAGS = -no-undefined -module -avoid-version \
     @APXS_LDFLAGS@ \
     @LIBXML2_LDFLAGS@ \
     @LUA_LDFLAGS@ \
-    @PCRE_LDFLAGS@
+    @PCRE_LDFLAGS@ \
+    @YAJL_LDFLAGS@
 endif
 
 if LINUX
diff --git a/apache2/modsecurity.c b/apache2/modsecurity.c
index 51341cac..1260f38c 100644
--- a/apache2/modsecurity.c
+++ b/apache2/modsecurity.c
@@ -256,8 +256,10 @@ static apr_status_t modsecurity_tx_cleanup(void *data) {
     /* XML processor cleanup. */
     if (msr->xml != NULL) xml_cleanup(msr);
 
+#ifdef WITH_YAJL
     /* JSON processor cleanup. */
     if (msr->json != NULL) json_cleanup(msr);
+#endif
 
     // TODO: Why do we ignore return code here?
     modsecurity_request_body_clear(msr, &my_error_msg);
diff --git a/apache2/modsecurity.h b/apache2/modsecurity.h
index 9ca11f2b..429806d3 100644
--- a/apache2/modsecurity.h
+++ b/apache2/modsecurity.h
@@ -59,7 +59,6 @@ typedef struct msc_parm msc_parm;
 #include "msc_lua.h"
 #endif
 
-
 #define PHASE_REQUEST_HEADERS       1
 #define PHASE_REQUEST_BODY          2
 #define PHASE_RESPONSE_HEADERS      3
@@ -369,7 +368,9 @@ struct modsec_rec {
     multipart_data      *mpd;                        /* MULTIPART processor data structure */
 
     xml_data            *xml;                        /* XML processor data structure       */
+#ifdef WITH_YAJL
     json_data           *json;                       /* JSON processor data structure      */
+#endif
 
     /* audit logging */
     char                *new_auditlog_boundary;
diff --git a/apache2/msc_json.c b/apache2/msc_json.c
index 91763d75..db7aa207 100644
--- a/apache2/msc_json.c
+++ b/apache2/msc_json.c
@@ -14,6 +14,8 @@
 
 #include "msc_json.h"
 
+#ifdef WITH_YAJL
+
 int json_add_argument(modsec_rec *msr, const char *value, unsigned length)
 {
     msc_arg *arg = (msc_arg *) NULL;
@@ -311,3 +313,4 @@ apr_status_t json_cleanup(modsec_rec *msr) {
     return 1;
 }
 
+#endif
diff --git a/apache2/msc_json.h b/apache2/msc_json.h
index 06fa6c82..91c887b3 100644
--- a/apache2/msc_json.h
+++ b/apache2/msc_json.h
@@ -14,11 +14,19 @@
 
 #ifndef _MSC_JSON_H_
 #define _MSC_JSON_H_
+#ifdef WITH_YAJL
 
 typedef struct json_data json_data;
 
+
 #include "modsecurity.h"
+
 #include <yajl/yajl_parse.h>
+//#ifdef WITH_YAJL
+//#else
+
+
+#include "modsecurity.h"
 
 /* Structures */
 struct json_data {
@@ -46,3 +54,4 @@ int DSOLOCAL json_complete(modsec_rec *msr, char **error_msg);
 apr_status_t DSOLOCAL json_cleanup(modsec_rec *msr);
 
 #endif
+#endif
diff --git a/apache2/msc_reqbody.c b/apache2/msc_reqbody.c
index 1d3f59ef..7d150eed 100644
--- a/apache2/msc_reqbody.c
+++ b/apache2/msc_reqbody.c
@@ -128,12 +128,19 @@ apr_status_t modsecurity_request_body_start(modsec_rec *msr, char **error_msg) {
             }
         }
         else if (strcmp(msr->msc_reqbody_processor, "JSON") == 0) {
+#ifdef WITH_YAJL
             if (json_init(msr, &my_error_msg) < 0) {
                 *error_msg = apr_psprintf(msr->mp, "JSON parsing error (init): %s", my_error_msg);
                 msr->msc_reqbody_error = 1;
                 msr->msc_reqbody_error_msg = my_error_msg;
                 msr_log(msr, 2, "%s", *error_msg);
             }
+#else
+            *error_msg = apr_psprintf(msr->mp, "JSON support was not enabled");
+            msr->msc_reqbody_error = 1;
+            msr->msc_reqbody_error_msg = my_error_msg;
+            msr_log(msr, 2, "%s", *error_msg);
+#endif
         }
         else if (strcmp(msr->msc_reqbody_processor, "URLENCODED") == 0) {
             /* Do nothing, URLENCODED processor does not support streaming yet. */
@@ -356,13 +363,20 @@ apr_status_t modsecurity_request_body_store(modsec_rec *msr,
             /* Increase per-request data length counter. */
             msr->msc_reqbody_no_files_length += length;
 
-            /* Process data as XML. */
+            /* Process data as JSON. */
+#ifdef WITH_YAJL
             if (json_process_chunk(msr, data, length, &my_error_msg) < 0) {
                 *error_msg = apr_psprintf(msr->mp, "JSON parsing error: %s", my_error_msg);
                 msr->msc_reqbody_error = 1;
                 msr->msc_reqbody_error_msg = *error_msg;
                 msr_log(msr, 2, "%s", *error_msg);
             }
+#else
+            *error_msg = apr_psprintf(msr->mp, "JSON support was not enabled");
+            msr->msc_reqbody_error = 1;
+            msr->msc_reqbody_error_msg = *error_msg;
+            msr_log(msr, 2, "%s", *error_msg);
+#endif
         }
         else if (strcmp(msr->msc_reqbody_processor, "URLENCODED") == 0) {
             /* Increase per-request data length counter. */
@@ -622,6 +636,7 @@ apr_status_t modsecurity_request_body_end(modsec_rec *msr, char **error_msg) {
             }
         }
         else if (strcmp(msr->msc_reqbody_processor, "JSON") == 0) {
+#ifdef WITH_YAJL
             if (json_complete(msr, &my_error_msg) < 0) {
                 *error_msg = apr_psprintf(msr->mp, "JSON parser error: %s", my_error_msg);
                 msr->msc_reqbody_error = 1;
@@ -629,6 +644,14 @@ apr_status_t modsecurity_request_body_end(modsec_rec *msr, char **error_msg) {
                 msr_log(msr, 2, "%s", *error_msg);
                  return -1;
              }
+#else
+            *error_msg = apr_psprintf(msr->mp, "JSON support was not enabled");
+            msr->msc_reqbody_error = 1;
+            msr->msc_reqbody_error_msg = *error_msg;
+            msr_log(msr, 2, "%s", *error_msg);
+            return -1;
+#endif
+
         }
         else if (strcmp(msr->msc_reqbody_processor, "URLENCODED") == 0) {
             return modsecurity_request_body_end_urlencoded(msr, error_msg);
diff --git a/build/find_yajl.m4 b/build/find_yajl.m4
new file mode 100644
index 00000000..05c1aa6e
--- /dev/null
+++ b/build/find_yajl.m4
@@ -0,0 +1,153 @@
+dnl Check for YAJL Libraries
+dnl CHECK_YAJL(ACTION-IF-FOUND [, ACTION-IF-NOT-FOUND])
+dnl Sets:
+dnl  YAJL_CFLAGS
+dnl  YAJL_LDADD
+dnl  YAJL_LDFLAGS
+dnl  YAJL_LIBS
+
+AC_DEFUN([CHECK_YAJL],
+[dnl
+
+AC_REQUIRE([PKG_PROG_PKG_CONFIG])
+
+YAJL_CONFIG=""
+YAJL_VERSION=""
+YAJL_CFLAGS=""
+YAJL_CPPFLAGS=""
+YAJL_LDADD=""
+YAJL_LDFLAGS=""
+YAJL_CONFIG=${PKG_CONFIG}
+YAJL_PKGNAMES="yajl2 yajl"
+YAJL_SONAMES="so la sl dll dylib"
+
+AC_ARG_WITH(
+    yajl,
+    [AC_HELP_STRING([--with-yajl=PATH],[Path to yajl prefix or config script])]
+    ,, with_yajl=yes)
+
+AS_CASE(["${with_yajl}"],
+  [no], [test_paths=],
+  [yes], [test_paths="/usr/local/libyajl /usr/local/yajl /usr/local /opt/libyajl /opt/yajl /opt /usr"],
+  [test_paths="${with_yajl}"])
+
+AS_IF([test "x${test_paths}" != "x"], [
+AC_MSG_CHECKING([for libyajl config script])
+for x in ${test_paths}; do
+    dnl # Determine if the script was specified and use it directly
+    if test ! -d "$x" -a -e "$x"; then
+        YAJL_CONFIG=$x
+        break
+    fi
+
+    dnl # Try known config script names/locations
+    for y in $YAJL_CONFIG; do
+        if test -e "${x}/bin/${y}"; then
+            YAJL_CONFIG="${x}/bin/${y}"
+            yajl_config="${YAJL_CONFIG}"
+            break
+        elif test -e "${x}/${y}"; then
+            YAJL_CONFIG="${x}/${y}"
+            yajl_config="${YAJL_CONFIG}"
+            break
+        fi
+    done
+    if test -n "${yajl_config}"; then
+        break
+    fi
+done
+
+dnl # Try known package names
+if test -n "${YAJL_CONFIG}"; then
+    YAJL_PKGNAME=""
+    for x in ${YAJL_PKGNAMES}; do
+        if ${YAJL_CONFIG} --exists ${x}; then
+            YAJL_PKGNAME="$x"
+            break
+        fi
+    done
+fi
+
+if test -n "${YAJL_PKGNAME}"; then
+    AC_MSG_RESULT([${YAJL_CONFIG}])
+    YAJL_VERSION="`${YAJL_CONFIG} ${YAJL_PKGNAME} --modversion`"
+    if test "$verbose_output" -eq 1; then AC_MSG_NOTICE(yajl VERSION: $YAJL_VERSION); fi
+    YAJL_CFLAGS="`${YAJL_CONFIG} ${YAJL_PKGNAME} --cflags`"
+    if test "$verbose_output" -eq 1; then AC_MSG_NOTICE(yajl CFLAGS: $YAJL_CFLAGS); fi
+    YAJL_LDADD="`${YAJL_CONFIG} ${YAJL_PKGNAME} --libs-only-l`"
+    if test "$verbose_output" -eq 1; then AC_MSG_NOTICE(yajl LDADD: $YAJL_LDADD); fi
+    YAJL_LDFLAGS="`${YAJL_CONFIG} ${YAJL_PKGNAME} --libs-only-L --libs-only-other`"
+    if test "$verbose_output" -eq 1; then AC_MSG_NOTICE(yajl LDFLAGS: $YAJL_LDFLAGS); fi
+else
+    AC_MSG_RESULT([no])
+
+    dnl Hack to just try to find the lib and include
+    AC_MSG_CHECKING([for yajl install])
+    for x in ${test_paths}; do
+        for y in ${YAJL_SONAMES}; do
+           if test -e "${x}/libyajl.${y}"; then
+                yajl_lib_path="${x}/"
+                yajl_lib_name="yajl"
+                break
+            else
+                yajl_lib_path=""
+                yajl_lib_name=""
+            fi
+        done
+        if test -n "$yajl_lib_path"; then
+            break
+        fi
+    done
+    for x in ${test_paths}; do
+        if test -e "${x}/include/yajl.h"; then
+            yajl_inc_path="${x}/include"
+            break
+        elif test -e "${x}/yajl.h"; then
+            yajl_inc_path="${x}"
+            break
+        fi
+
+        dnl # Check some sub-paths as well
+        for yajl_pkg_name in ${yajl_lib_name} ${YAJL_PKGNAMES}; do
+            if test -e "${x}/include/${yajl_pkg_name}/yajl.h"; then
+                yajl_inc_path="${x}/include"
+                break
+            elif test -e "${x}/${yajl_pkg_name}/yajl.h"; then
+                yajl_inc_path="${x}"
+                break
+            else
+                yajl_inc_path=""
+            fi
+        done
+        if test -n "$yajl_inc_path"; then
+            break
+        fi
+    done
+    if test -n "${yajl_lib_path}" -a -n "${yajl_inc_path}"; then
+        YAJL_CONFIG=""
+        AC_MSG_RESULT([${yajl_lib_path} ${yajl_inc_path}])
+        YAJL_VERSION="2"
+        YAJL_CFLAGS="-I${yajl_inc_path}"
+        YAJL_LDADD="-l${yajl_lib_name}"
+        YAJL_LDFLAGS="-L${yajl_lib_path}"
+    else
+        YAJL_VERSION=""
+        AC_MSG_RESULT([no])
+    fi
+fi
+
+])
+
+YAJL_LIBS=${YAJL_LDADD}
+AC_SUBST(YAJL_CFLAGS)
+AC_SUBST(YAJL_LDADD)
+AC_SUBST(YAJL_LIBS)
+AC_SUBST(YAJL_LDFLAGS)
+    if test -z "${YAJL_VERSION}"; then
+      ifelse([$2], , AC_MSG_NOTICE([optional yajl library not found]), $2)
+    else
+      AC_MSG_NOTICE([using yajl v${YAJL_VERSION}])
+      YAJL_CFLAGS="-DWITH_YAJL ${YAJL_CFLAGS}"
+      ifelse([$1], , , $1) 
+    fi 
+])
diff --git a/configure.ac b/configure.ac
index 175e893d..5f47ca47 100644
--- a/configure.ac
+++ b/configure.ac
@@ -699,7 +699,8 @@ CHECK_CURL()
 fi
 
 # Check for YAJL libs (for JSON body processor)
-AC_SEARCH_LIBS([yajl_alloc], [yajl])
+CHECK_YAJL()
+#AC_SEARCH_LIBS([yajl_alloc], [yajl])
 
 AC_CONFIG_FILES([Makefile])
 AC_CONFIG_FILES([tools/Makefile])
diff --git a/standalone/Makefile.am b/standalone/Makefile.am
index c555cc2d..f801d97c 100644
--- a/standalone/Makefile.am
+++ b/standalone/Makefile.am
@@ -47,7 +47,8 @@ standalone_la_CFLAGS = -DVERSION_NGINX \
     @LIBXML2_CFLAGS@ \
     @LUA_CFLAGS@ \
     @MODSEC_EXTRA_CFLAGS@ \
-    @PCRE_CFLAGS@
+    @PCRE_CFLAGS@ \
+    @YAJL_CFLAGS@
 
 standalone_la_CPPFLAGS = @APR_CPPFLAGS@ \
     @LIBXML2_CPPFLAGS@ \
@@ -57,7 +58,8 @@ standalone_la_LIBADD = @APR_LDADD@ \
     @APU_LDADD@ \
     @LIBXML2_LDADD@ \
     @LUA_LDADD@ \
-    @PCRE_LDADD@
+    @PCRE_LDADD@ \
+    @YAJL_LDADD@
 
 if AIX
 standalone_la_LDFLAGS = -module -avoid-version \
@@ -66,7 +68,8 @@ standalone_la_LDFLAGS = -module -avoid-version \
     @APXS_LDFLAGS@ \
     @LIBXML2_LDFLAGS@ \
     @LUA_LDFLAGS@ \
-    @PCRE_LDFLAGS@
+    @PCRE_LDFLAGS@ \
+    @YAJL_LDFLAGS@
 endif
 
 if HPUX
@@ -76,7 +79,8 @@ standalone_la_LDFLAGS = -module -avoid-version \
     @APXS_LDFLAGS@ \
     @LIBXML2_LDFLAGS@ \
     @LUA_LDFLAGS@ \
-    @PCRE_LDFLAGS@
+    @PCRE_LDFLAGS@ \
+    @YAJL_LDFLAGS@
 endif
 
 if MACOSX
@@ -86,7 +90,8 @@ standalone_la_LDFLAGS = -module -avoid-version \
     @APXS_LDFLAGS@ \
     @LIBXML2_LDFLAGS@ \
     @LUA_LDFLAGS@ \
-    @PCRE_LDFLAGS@
+    @PCRE_LDFLAGS@ \
+    @YAJL_LDFLAGS@
 endif
 
 if SOLARIS
@@ -96,7 +101,8 @@ standalone_la_LDFLAGS = -module -avoid-version \
     @APXS_LDFLAGS@ \
     @LIBXML2_LDFLAGS@ \
     @LUA_LDFLAGS@ \
-    @PCRE_LDFLAGS@
+    @PCRE_LDFLAGS@ \
+    @YAJL_LDFLAGS@
 endif
 
 if LINUX
@@ -106,7 +112,8 @@ standalone_la_LDFLAGS = -no-undefined -module -avoid-version \
     @APXS_LDFLAGS@ \
     @LIBXML2_LDFLAGS@ \
     @LUA_LDFLAGS@ \
-    @PCRE_LDFLAGS@
+    @PCRE_LDFLAGS@ \
+    @YAJL_LDFLAGS@
 endif
 
 if FREEBSD
@@ -116,7 +123,8 @@ standalone_la_LDFLAGS = -no-undefined -module -avoid-version \
     @APXS_LDFLAGS@ \
     @LIBXML2_LDFLAGS@ \
     @LUA_LDFLAGS@ \
-    @PCRE_LDFLAGS@
+    @PCRE_LDFLAGS@ \
+    @YAJL_LDFLAGS@
 endif
 
 if OPENBSD
@@ -126,7 +134,8 @@ standalone_la_LDFLAGS = -no-undefined -module -avoid-version \
     @APXS_LDFLAGS@ \
     @LIBXML2_LDFLAGS@ \
     @LUA_LDFLAGS@ \
-    @PCRE_LDFLAGS@
+    @PCRE_LDFLAGS@ \
+    @YAJL_LDFLAGS@
 endif
 
 if NETBSD
@@ -136,5 +145,6 @@ standalone_la_LDFLAGS = -no-undefined -module -avoid-version \
     @APXS_LDFLAGS@ \
     @LIBXML2_LDFLAGS@ \
     @LUA_LDFLAGS@ \
-    @PCRE_LDFLAGS@
+    @PCRE_LDFLAGS@ \
+    @YAJL_LDFLAGS@
 endif
diff --git a/tests/Makefile.am b/tests/Makefile.am
index 74f8fe0d..f7f5c001 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -6,6 +6,7 @@ msc_test_SOURCES = msc_test.c \
     $(top_srcdir)/apache2/msc_crypt.c \
     $(top_srcdir)/apache2/msc_geo.c \
     $(top_srcdir)/apache2/msc_gsb.c \
+    $(top_srcdir)/apache2/msc_json.c \
     $(top_srcdir)/apache2/msc_logging.c \
     $(top_srcdir)/apache2/msc_lua.c \
     $(top_srcdir)/apache2/msc_multipart.c \
@@ -32,7 +33,8 @@ msc_test_CFLAGS = @APR_CFLAGS@ \
     @LIBXML2_CFLAGS@ \
     @LUA_CFLAGS@ \
     @MODSEC_EXTRA_CFLAGS@ \
-    @PCRE_CFLAGS@
+    @PCRE_CFLAGS@ \
+    @YAJL_CFLAGS@
     
 msc_test_CPPFLAGS = -I$(top_srcdir)/apache2 \
     @APR_CPPFLAGS@ \
@@ -43,14 +45,16 @@ msc_test_LDADD = @APR_LDADD@ \
     @APU_LDADD@ \
     @LIBXML2_LDADD@ \
     @LUA_LDADD@ \
-    @PCRE_LDADD@
+    @PCRE_LDADD@ \
+    @YAJL_LDADD@
 
 msc_test_LDFLAGS = @APR_LDFLAGS@ \
     @APU_LDFLAGS@ \
     @APXS_LDFLAGS@ \
     @LIBXML2_LDFLAGS@ \
     @LUA_LDFLAGS@ \
-    @PCRE_LDFLAGS@
+    @PCRE_LDFLAGS@ \
+    @YAJL_LDFLAGS@
 
 check_SCRIPTS = run-unit-tests.pl
 TESTS = $(check_SCRIPTS)