After the last updates 2? days ago, aptana 3 does not start properly anymore.
I tried sun's java 6 and openjdk under debian testing.
A fresh download does work, using the old workspace leads to the same problem anyway.
Problem seems to be a file in the workspace/.metadata folder.
I compressed an instance of aptana including the workspace, please find it here:
hennr.name/apatana-3.0.4.tar.xz (32 bit version, compressed with xz)
Let me know if you need further information.