[ANT] Load different jar files while depending on different project version

[Kit]

Can anyone please help?

In the following classpath, the commonTools.jar is only defined in
"2.1.0.0", but not in "2.0.0.0", I have tried using <if>, which is not
supported by path:

<!-- Override these two to change obs version -->
<property name="project.jar.version" value="2.1.0.0" />

<path id="project-dep.classpath">
<pathelement location="${project.lib.dir}project/$
{project.jar.version}/corbautil.jar"/>
<pathelement location="${project.lib.dir}project/$
{project.jar.version}/idl-java.jar"/>
<pathelement location="${project.lib.dir}project/$
{project.jar.version}/obs.jar"/>
<pathelement location="${project.lib.dir}project/$
{project.jar.version}/securityServer.jar"/>
<pathelement location="${project.lib.dir}project/$
{project.jar.version}/synapse.jar"/>
<pathelement location="${project.lib.dir}project/$
{project.jar.version}/commonTools.jar"/>
</path>

Do you know how to exclude this specific jar automatically when I
change the version value from "2.1.0.0" to "2.0.0.0" ?