diff --git a/drools-compiler/pom.xml b/drools-compiler/pom.xml
index 653bb265ff7..927945346da 100644
--- a/drools-compiler/pom.xml
+++ b/drools-compiler/pom.xml
@@ -139,30 +139,16 @@
                     <condition property="antlr.debugParser" value="-Xconversiontimeout 32000 -debug" else="">
                       <isset property="debugParser"/>
                     </condition>
-                    <condition property="antlr.debugWalker" value="-Xconversiontimeout 32000 -debug" else="">
-                      <isset property="debugWalker"/>
-                    </condition>
-                    <echo message="Generating Antlr Parser (${antlr.debugParser})"/>
-                    <java classname="org.antlr.Tool" fork="true">
-                      <jvmarg line="-Xmx750M -Xincgc"/>
-                      <arg line="${antlr.debugParser} -lib src/main/resources/org/drools/lang src/main/resources/org/drools/lang/DRL.g"/>
-                      <classpath refid="maven.compile.classpath"/>
-                    </java>
-                    <echo message="Generating Antlr Walker (${antlr.debugWalker})"/>
-                    <java classname="org.antlr.Tool" fork="true">
-                      <jvmarg line="-Xmx750M -Xincgc"/>
-                      <arg line="${antlr.debugWalker} -lib src/main/resources/org/drools/lang src/main/resources/org/drools/lang/DescrBuilderTree.g"/>
-                      <classpath refid="maven.compile.classpath"/>
-                    </java>
-                    <echo message="Generating Antlr Legacy Parser/Walker for DRL 5.x"/>
+                    <echo message="Generating Lexer (${antlr.debugParser})"/>
                     <java classname="org.antlr.Tool" fork="true">
                       <jvmarg line="-Xmx750M -Xincgc"/>
-                      <arg line="-lib src/main/resources/org/drools/lang src/main/resources/org/drools/lang/DRL5x.g"/>
+                      <arg line="${antlr.debugParser} -lib src/main/resources/org/drools/lang src/main/resources/org/drools/lang/DRLLexer.g"/>
                       <classpath refid="maven.compile.classpath"/>
                     </java>
+                    <echo message="Generating Expressions Parser (${antlr.debugParser})"/>
                     <java classname="org.antlr.Tool" fork="true">
                       <jvmarg line="-Xmx750M -Xincgc"/>
-                      <arg line="-lib src/main/resources/org/drools/lang src/main/resources/org/drools/lang/DescrBuilderTree5x.g"/>
+                      <arg line="${antlr.debugParser} -lib src/main/resources/org/drools/lang src/main/resources/org/drools/lang/DRLExpressions.g"/>
                       <classpath refid="maven.compile.classpath"/>
                     </java>
                     <move todir="src/main/java/org/drools/lang/">
@@ -170,16 +156,6 @@
                         <include name="**/*.java"/>
                       </fileset>
                     </move>
-                    <echo message="Generating Antlr Tree2TestDRL.g"/>
-                    <java classname="org.antlr.Tool" fork="true">
-                      <arg line="-lib src/main/resources/org/drools/lang src/main/resources/org/drools/lang/Tree2TestDRL.g"/>
-                      <classpath refid="maven.compile.classpath"/>
-                    </java>
-                    <move todir="src/test/java/org/drools/lang/">
-                      <fileset dir="src/main/resources/org/drools/lang">
-                        <include name="**/*.java"/>
-                      </fileset>
-                    </move>
                     <echo message="Generating Antlr DSLMap.g and DSLMapWalker.g"/>
                     <java classname="org.antlr.Tool" fork="true">
                       <arg line="-lib src/main/resources/org/drools/lang/dsl src/main/resources/org/drools/lang/dsl/DSLMap.g src/main/resources/org/drools/lang/dsl/DSLMapWalker.g"/>