<project name="test" default="all" basedir="."> <target name="init"> <javac srcdir="tasksource" destdir="tasksource"/> <jar jarfile="mytasks.jar" basedir="tasksource"> <exclude name="**/*.java"/> </jar> <taskdef name="customtask" classname="com.mycom.MyCustomTask"> <classpath> <pathelement location="mytasks.jar"/> </classpath> </taskdef> </target> <target name="all" depends="init"> <customtask someparam="val"/> </target> </project>