I don't think that's true. Module::Build calls upon ExtUtils::Manifest to check the completeness of the MANIFEST in the "distcheck" action or to update the MANIFEST for the "manifest" action. That should use a MANIFEST.SKIP file, if one exists.
To the original poster, could you please give an example of what's in your MANIFEST.SKIP that isn't working and perhaps show some output from a "Build distcheck" action?
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