[news.eclipse.newcomer] External ant classpath

[cbrown@xxxxxxxxxx (cbrown)]

  I need help setting the classpath for an external ant build file in a 
manner that will work for a team of developers working on differnt 
machines - i.e., when external packages aren't always installed in the 
same place.

 I have a build.xml file like;

<project default="mine">
 <target name="mine" >
   <java dir="." fork="true" classname="myPackage.myClass">
     <arg value="myDoc.xml" />
   </java>
 </target>
</project>

 I have tried;

- placing a link to myPackage.jar in ~/.ant/lib
- adding an environment variable 'export MY_HOME=myPath', and adding an 
entry for ${env_var:MY_HOME}/myPackage.jar to the ant Runtime preferences
- using
 <classpath>
   <pathelement location="${env.MY_HOME}/myPackage.jar"/>
 </classpath>
- using
 <classpath>
   <pathelement path="${java.class.path}"/>
 </classpath>
- a couple of other variations I can't recall.

  Also, is there a mechanism that works for both IDE builds and external 
builders?  I.e., a way to define the classpath once and have it work 
throughout?

  Thank you for your help.