I'd like to ONLY exclude certain files in maven-war-plugin when property "skipCompress" set to true, I thought I could do something like this, but it doesn't work for me. BTW, I can't use profile to achieve this even I want to use skipCompress to turn on and off the compression in both development and deployment profiles.

<plugin>
    <artifactId>maven-war-plugin</artifactId>
    <configuration>
    <if>
        <not>
        <equals arg1="${skipCompress}" arg2 = "true"/>
        </not>
        <then>
        <warSourceExcludes>**/external/dojo/**/*.js</warSourceExcludes>
        </then>
    </if>
    </configuration>
</plugin>

Thanks,

David