1) Copy the file ant-eclipse-1.0-jvm1.2.jar to the directory "lib" within the
Ant installation directory or put it into the CLASSPATH before running Ant.

2) Declare the task in the Ant build script to process:

<taskdef name="eclipse" classname="prantl.ant.eclipse.EclipseTask"
  classpath="<path>/ant-eclipse-1.0-jvm1.2.jar" />

The attribute "classpath" is necessary only if the task cannot be found in the
CLASSPATH of the Ant process.