Eclipse problem: not compiling module projects

[Jeanette Winzenburg]

Just a quick question to Eclipse users (who do compile with Eclipse,  
not with gradle)

Problem:

updated my Eclipse to the december release yesterday, now it doesn't  
compile (neither automatically, nor forcing a clean build) anything as  
soon as the module projects are included, neither the modules nor  
dependent projects - nothing else changed (hopefully ;). All fine when  
adding the compiled module-jars.

Questions:

- anybody else seeing it?
- any ideas where to look?

-- Jeanette