diff --git a/apache2/apache2_config.c b/apache2/apache2_config.c
index 3ab618a9..ce97950f 100644
--- a/apache2/apache2_config.c
+++ b/apache2/apache2_config.c
@@ -799,7 +799,8 @@ static const char *add_rule(cmd_parms *cmd, directory_config *dcfg, int type,
         return my_error_msg;
     }
 
-    /* Rules must have uniq ID */
+#ifndef ALLOW_ID_NOT_UNIQUE
+	/* Rules must have uniq ID */
     type_rule = (dcfg->tmp_chain_starter == NULL);
 #if defined(WITH_LUA)
             type_rule = (type != RULE_TYPE_LUA && type_rule);
@@ -831,6 +832,7 @@ static const char *add_rule(cmd_parms *cmd, directory_config *dcfg, int type,
             //    return "ModSecurity: Found another rule with the same id";
         }
     }
+#endif
 
     /* Create default actionset if one does not already exist. */
     if (dcfg->tmp_default_actionset == NULL) {
diff --git a/configure.ac b/configure.ac
index 0f32b01b..fd576e6e 100644
--- a/configure.ac
+++ b/configure.ac
@@ -411,6 +411,22 @@ AC_ARG_ENABLE(request-early,
   request_early='-DREQUEST_EARLY'
 ])
 
+# Enable duplicate rules id
+AC_ARG_ENABLE(rule-id-validation,
+              AS_HELP_STRING([--enable-rule-id-validation],
+                             [Forbid duplicate rule ids and missing ones. This is the default]),
+[
+  if test "$enableval" != "no"; then
+    unique_id=
+  else
+    unique_id="-DALLOW_ID_NOT_UNIQUE"
+    MODSEC_EXTRA_CFLAGS="$MODSEC_EXTRA_CFLAGS $unique_id"
+  fi
+],
+[
+  unique_id=''
+])
+
 # Ignore configure errors
 AC_ARG_ENABLE(errors,
               AS_HELP_STRING([--disable-errors],