CXF 2.1 and previous provides ant tasks for wsdl2java and java2ws. These tasks are not in CXF 2.2, since it's simple enough to use <java/>.
The tasks are delivered in a separate jar file: modules/integration/cxf-anttasks-2.1.jar.
Here is a snippet from the wsdl_first_anttask sample provided in the CXF distribution. It shows the declaration of the task jar file via the ant 'antlib' mechanisms, and the use of the wsdl2java task.
<project name="hello world demo" default="build" basedir="."
xmlns:cxf="antlib:org.apache.cxf.ant.extensions" >
<import file="../common_build.xml"/>
<path id='cxf.anttasks.classpath'>
<pathelement location='${cxf.home}/modules/integration/cxf-anttasks-2.1.jar'/>
<path refid='cxf.classpath'/>
</path>
<taskdef uri="antlib:org.apache.cxf.ant.extensions"
resource="org/apache/cxf/ant/extensions/antlib.xml"
classpathref="cxf.anttasks.classpath"/>
<target name="generate.code">
<echo level="info" message="Generating code using wsdl2java..."/>
<mkdir dir="${build.src.dir}"/>
<mkdir dir="${build.classes.dir}"/>
<cxf:wsdl2java wsdl="${wsdl.dir}/hello_world.wsdl"
sourceDestDir="${build.src.dir}"
destDir="${build.classes.dir}"/>
</target>
</project>
Note you may always use the Ant <java/> task directly instead and with the same options as available with the command-line wsdl2java and java2ws (CXF 2.1) or java2wsdl (CXF 2.0.x) options. Examples of such usage are on the tools' respective pages.