diff --git a/pmd-visualforce/etc/grammar/VfParser.jjt b/pmd-visualforce/etc/grammar/VfParser.jjt
index e7c0bae418..d8725ddaa7 100644
--- a/pmd-visualforce/etc/grammar/VfParser.jjt
+++ b/pmd-visualforce/etc/grammar/VfParser.jjt
@@ -145,7 +145,7 @@ PARSER_END(VfParser)
 	| <GE: ">=" >
 	| <LT: "<" >
 	| <GT: ">" >
-	| <EXCL: ("!"|"~"|"NOT") >
+	| <EXCL: ("!"|"~") >
 	| <PIPE_PIPE: "||" >
 	| <STRING_LITERAL: <QUOTED_STRING> >
 	| <DIGITS: (<NUM_CHAR>)+ (<DOT> (<NUM_CHAR>)+)? >
@@ -476,10 +476,10 @@ void UnaryExpression()  #void :
 {}
 {
 	  ( <PLUS> | <MINUS> ) UnaryExpression()
-	|  UnaryExpressionNotPlusMinus()
+	|  NegationExpression()
 }
 
-void UnaryExpressionNotPlusMinus() #void :
+void NegationExpression() #void :
 {}
 {
   ( <EXCL> ) UnaryExpression()
diff --git a/pmd-visualforce/src/main/java/net/sourceforge/pmd/lang/vf/ast/VfParserVisitorAdapter.java b/pmd-visualforce/src/main/java/net/sourceforge/pmd/lang/vf/ast/VfParserVisitorAdapter.java
index ec3d9d3a46..a0fd42ba2a 100644
--- a/pmd-visualforce/src/main/java/net/sourceforge/pmd/lang/vf/ast/VfParserVisitorAdapter.java
+++ b/pmd-visualforce/src/main/java/net/sourceforge/pmd/lang/vf/ast/VfParserVisitorAdapter.java
@@ -93,5 +93,5 @@ public class VfParserVisitorAdapter implements VfParserVisitor {
     public Object visit(ASTContent node, Object data) {
         return visit((VfNode) node, data);
     }
-
+    
 }
diff --git a/pmd-visualforce/src/main/java/net/sourceforge/pmd/lang/vf/rule/security/VfUnescapeElRule.java b/pmd-visualforce/src/main/java/net/sourceforge/pmd/lang/vf/rule/security/VfUnescapeElRule.java
index ff7124e816..486bd82e81 100644
--- a/pmd-visualforce/src/main/java/net/sourceforge/pmd/lang/vf/rule/security/VfUnescapeElRule.java
+++ b/pmd-visualforce/src/main/java/net/sourceforge/pmd/lang/vf/rule/security/VfUnescapeElRule.java
@@ -230,20 +230,24 @@ public class VfUnescapeElRule extends AbstractVfRule {
         if (expression != null) {
             final ASTIdentifier id = expression.getFirstChildOfType(ASTIdentifier.class);
             if (id != null) {
-                switch (id.getImage().toLowerCase()) {
-                case "$component":
-                case "$objecttype":
-                case "$label":
-                case "$resource":
-                case "urlfor":
-                case "$site":
-                case "$page":
-                case "$action":
-                case "casesafeid":
-                case "$remoteaction":
-                    return true;
+                List<ASTArguments> args = expression.findChildrenOfType(ASTArguments.class);
+                if (!args.isEmpty()) {
+                    switch (id.getImage().toLowerCase()) {
+                    case "$component":
+                    case "$objecttype":
+                    case "$label":
+                    case "$resource":
+                    case "urlfor":
+                    case "$site":
+                    case "$page":
+                    case "$action":
+                    case "casesafeid":
+                    case "not":
+                    case "$remoteaction":
+                        return true;
 
-                default:
+                    default:
+                    }
                 }
             }
 
diff --git a/pmd-visualforce/src/test/resources/net/sourceforge/pmd/lang/vf/rule/security/xml/VfUnescapeEl.xml b/pmd-visualforce/src/test/resources/net/sourceforge/pmd/lang/vf/rule/security/xml/VfUnescapeEl.xml
index 8c4c8ed50c..cd698c2bca 100644
--- a/pmd-visualforce/src/test/resources/net/sourceforge/pmd/lang/vf/rule/security/xml/VfUnescapeEl.xml
+++ b/pmd-visualforce/src/test/resources/net/sourceforge/pmd/lang/vf/rule/security/xml/VfUnescapeEl.xml
@@ -557,5 +557,20 @@ Safe unquoted followed by safe quoted
 ]]></code>
 		<source-type>vf</source-type>
 	</test-code>
+	<test-code>
+		<description><![CDATA[
+NOT method evaluates to safe boolean
+     ]]></description>
+		<expected-problems>0</expected-problems>
+		<code><![CDATA[
+<apex:page>
+	<script>
+		if({!NOT(yes)}) { maskFormEls(); }
+	</script>
+</apex:page>
+]]></code>
+		<source-type>vf</source-type>
+	</test-code>
+
 
 </test-data>