Under normal conditions I would not have run into this as my .launch
and .classpath profiles would always match, however migrating the
project from 1.0.21 this wasn't 100% the case.
I had included two versions of google maps in my project and was coming
up with errors were GWT was getting confused over which class it was
loading (from what I could see it was compiling both versions from the
jar files and causing some really unpredictable results and low level
exceptions).
A word to the wise... double check your classpath and make 100% sure
you don't have duplicates.
On the GWT side, perhaps this condition should generate a compiler
error saything something like ambiguous reference....