It's fairly dirty code...  pjse.FileTable.GFT.CurrentPackage is a much better thing to be using under the circumstances.  And there's no reason for currentPackage to be static...

currentPackage could not have been null or the button would have been disabled, though... (Of course, as it was static, something else could have reset the value elsewhere after the test had been made.  I think it must have been getting set to the package for the requested BHAV somehow - but I can't think how...) 

The PreRelease CVS branch contains the source we built the latest release from (and maybe later changes).  HEAD gets synched to PreRelease once we ship (and before any later changes!), so it's possible for it to be slightly out of date briefly but is intended to reflect the latest release.