diff --git a/CHANGES b/CHANGES
index d0480e2c..0bd0210a 100644
--- a/CHANGES
+++ b/CHANGES
@@ -1,6 +1,8 @@
 05 Mar 2009 - 2.5.9-dev1
 ------------------------
 
+ * Added macro expansion for append/prepend action.
+
  * Fixed race condition in concurrent updates of persistent counters.  Updates
    are now atomic.
 
diff --git a/apache2/re_actions.c b/apache2/re_actions.c
index d18df4ae..b15f568c 100644
--- a/apache2/re_actions.c
+++ b/apache2/re_actions.c
@@ -1803,8 +1803,18 @@ static apr_status_t msre_action_exec_execute(modsec_rec *msr, apr_pool_t *mptmp,
 static apr_status_t msre_action_prepend_execute(modsec_rec *msr, apr_pool_t *mptmp,
     msre_rule *rule, msre_action *action)
 {
-    msr->content_prepend = action->param;
-    msr->content_prepend_len = strlen(action->param);
+    msc_string *var = NULL;
+
+    /* Expand any macros in the text */
+    var = apr_pcalloc(mptmp, sizeof(msc_string));
+    if (var == NULL) return -1;
+    var->value = (char *)action->param;
+    var->value_len = strlen(var->value);
+    expand_macros(msr, var, rule, mptmp);
+
+    /* ENH: Verify we really have to dup the data here. */
+    msr->content_prepend = apr_pstrndup(msr->mp, var->value, var->value_len);
+    msr->content_prepend_len = var->value_len;
 
     return 1;
 }
@@ -1813,8 +1823,18 @@ static apr_status_t msre_action_prepend_execute(modsec_rec *msr, apr_pool_t *mpt
 static apr_status_t msre_action_append_execute(modsec_rec *msr, apr_pool_t *mptmp,
     msre_rule *rule, msre_action *action)
 {
-    msr->content_append = action->param;
-    msr->content_append_len = strlen(action->param);
+    msc_string *var = NULL;
+
+    /* Expand any macros in the text */
+    var = apr_pcalloc(mptmp, sizeof(msc_string));
+    if (var == NULL) return -1;
+    var->value = (char *)action->param;
+    var->value_len = strlen(var->value);
+    expand_macros(msr, var, rule, mptmp);
+
+    /* ENH: Verify we really have to dup the data here. */
+    msr->content_append = apr_pstrndup(msr->mp, var->value, var->value_len);
+    msr->content_append_len = var->value_len;
 
     return 1;
 }
diff --git a/apache2/t/regression/action/00-misc.t b/apache2/t/regression/action/00-misc.t
index 0a99b4c5..1629d697 100644
--- a/apache2/t/regression/action/00-misc.t
+++ b/apache2/t/regression/action/00-misc.t
@@ -1,6 +1,5 @@
 ### Test misc actions
 
-# TODO: append
 # TODO: block
 # TODO: capture
 # TODO: chain
@@ -10,7 +9,6 @@
 # TODO: initcol
 # TODO: multiMatch
 # TODO: pause
-# TODO: prepend
 # TODO: sanitiseArg
 # TODO: sanitiseMatched
 # TODO: sanitiseRequestHeader
diff --git a/apache2/t/regression/action/10-append-prepend.t b/apache2/t/regression/action/10-append-prepend.t
new file mode 100644
index 00000000..97f28685
--- /dev/null
+++ b/apache2/t/regression/action/10-append-prepend.t
@@ -0,0 +1,49 @@
+# TODO: Need more tests here
+
+### append
+{
+	type => "action",
+	comment => "append content",
+	conf => qq(
+		SecRuleEngine On
+        SecContentInjection On
+		SecDebugLog "$ENV{DEBUG_LOG}"
+		SecDebugLogLevel 9
+		SecAction "phase:1,setvar:tx.test=test"
+		SecAction "phase:2,append:'APPEND: \%{tx.test}'"
+	),
+	match_log => {
+        debug => [ "Added content to bottom: APPEND: test", 1 ],
+	},
+	match_response => {
+		status => qr/^200$/,
+		content => qr/APPEND: test$/,
+	},
+	request => new HTTP::Request(
+		GET => "http://$ENV{SERVER_NAME}:$ENV{SERVER_PORT}/test.txt",
+	),
+},
+
+### prepend
+{
+	type => "action",
+	comment => "prepend content",
+	conf => qq(
+		SecRuleEngine On
+        SecContentInjection On
+		SecDebugLog "$ENV{DEBUG_LOG}"
+		SecDebugLogLevel 9
+		SecAction "phase:1,setvar:tx.test=test"
+		SecAction "phase:2,prepend:'PREPEND: \%{tx.test}'"
+	),
+	match_log => {
+        debug => [ "Added content to top: PREPEND: test", 1 ],
+	},
+	match_response => {
+		status => qr/^200$/,
+		content => qr/^PREPEND: test/,
+	},
+	request => new HTTP::Request(
+		GET => "http://$ENV{SERVER_NAME}:$ENV{SERVER_PORT}/test.txt",
+	),
+},
diff --git a/doc/modsecurity2-apache-reference.xml b/doc/modsecurity2-apache-reference.xml
index fff38f8b..421c33f6 100644
--- a/doc/modsecurity2-apache-reference.xml
+++ b/doc/modsecurity2-apache-reference.xml
@@ -4270,6 +4270,12 @@ SecAction phase:3,allow</programlisting>
       <para>Example:</para>
 
       <programlisting>SecRule RESPONSE_CONTENT_TYPE "^text/html" "nolog,pass,<emphasis>append:'&lt;hr&gt;Footer'</emphasis>"</programlisting>
+
+      <note>
+        <para>While macro expansion is allowed in the additional content, 
+        you are strongly cautioned against inserting user defined data
+        fields.</para>
+      </note>
     </section>
 
     <section>
@@ -4923,6 +4929,12 @@ SecRule REQUEST_HEADERS:User-Agent "Test" log,deny,status:403</programlisting>
       <para>Example:</para>
 
       <programlisting>SecRule RESPONSE_CONTENT_TYPE ^text/html "phase:3,nolog,pass,<emphasis>prepend:'Header&lt;br&gt;'</emphasis>"</programlisting>
+
+      <note>
+        <para>While macro expansion is allowed in the additional content, 
+        you are strongly cautioned against inserting user defined data
+        fields.</para>
+      </note>
     </section>
 
     <section>