Thx for all the input! So, when I post the final release, I'll make sure to add a comment next to/above the src.tar.gz, indicating this requires gnu tar.
Now, for the first item...
I don't see a problem unzipping the plugin zip files...Although I noticed Rick apparently saved the file as a zip.zip, instead of .zip...Not sure if that matters.
However, I noticed that there was a difference between how previous releases produced the zip file. Finally I figured out in a 'new' eclipse installation there was an option re Jar files checked on the 'Options' tab in the project export (once unchecked, it stays unchecked, even with new plugin projects). I'm not sure this is only with eclipse 3.1, but I'll make a note in the plugins/Readme.txt assuming it is eclipse 3.2, and that it should be unchecked.
Also with previous derby releases, the plugins were combined, instead of 2 separate zipfiles as I made them.
But, I thought it was a little strange to call the combined zip the same name as the single one, as was done with previous releases, so, I propose to give it a different name: derby_eclipse_plugins_1.1.0.zip.
I created a new 103 co, svn reverted to revision 548006 (the original 10.3.1.0beta revision), created the core ui, used the core ui created (rather than some old version as it says in the plugins/Readme.txt - although at this point it doesn't matter as the core ui has never changed), build the combo zip file and uploaded the new file to http://people.apache.org/~myrnavl/10.3.1.0.beta/derby_eclipse_plugins_1.1.0.zip.
Please have a look and see if that one unzips correctly...