Refusing to exclude file

No matter what I do I can't seem to get CMD to exclude a js file...I'm using Sencha Architect 3 to do the build. So it's generated me a build.xml file which loads build-impl.xml which loads init-impl.xml.

app.framework.version=4.2.1.883

app.cmd.version=4.0.4.84

I've tried placing the below into init-impl.xml which partially works. When Architect does the build I see the echos yet it refuses to honour the exclude property.

What am I doing wrong?

Code:

<target name="-before-init">
        <echo>Setting build.operations...</echo>
        <echo>app.dir=${app.dir}</echo>
        <property name="build.operations">
            exclude
                -file=\resources\js\version.js
        </property>
</target>