Groovy-TestNG-Ant running error - ant

Question

I've faced with next problem.
Trying to create pilot test-project using Groovy, TestNG, ant.
If I run tests from my IDE (Eclipse) - all is ok.
But when I try run tests using ant - not easy for me problem. Could you help me?
build.xml is present below.
Compile target - pass ok, but on runTest target I see problem:
"Exception in thread "main" java.lang.NoClassDefFoundError: groovy/lang/GroovyObject"
<project basedir="." default="runTest" name="Ant file for TestNG">
<property name="src" location="src" />
<property name="build" location="build" />
<property name="libs" location="lib" />
<path id="class.path">
<pathelement location="${libs}/testng.jar" />
<pathelement location="lib/testng.jar"/>
<pathelement location="${build}" />
</path>
<taskdef name="testng" classname="org.testng.TestNGAntTask">
<classpath>
<pathelement location="lib/groovy-all.jar"/>
<pathelement location="lib/testng.jar"/>
</classpath>
</taskdef>
<target name="runTest" depends="compile">
<mkdir dir="testng_output"/><!-- Create the output directory. -->
<testng outputdir="testng_output" classpathref="class.path">
<xmlfileset dir="." includes="testng.xml"/>
</testng>
</target>
<target name="compile">
<delete dir="build"/>
<mkdir dir="build"/>
<taskdef name="groovyc" classname="org.codehaus.groovy.ant.Groovyc" classpath="lib/groovy-all.jar"/>
<groovyc srcdir="src" destdir="./build">
<classpath>
<pathelement path="lib/groovy-all.jar"/>
<pathelement path="lib/testng.jar"/>
</classpath>
<javac source="1.7" target="1.7" debug="off" />
</groovyc>
</target>
</project>
And this is testng.xml
<suite name="My Test Suite" parallel="methods" thread-count="5">
<test name="My Test">
<classes>
<class name="test1" />
</classes>
</test>
</suite>