Today I started noticing a peculiar bug when editing Groovy classes that were Grails controllers (but no other classes, as far as I can tell).
1) I open a Grails controller class source file and, once inspection is complete, I get a green or yellow status box at the top of the right gutter.
2) I then make any change to the file, including simply selecting some text, copying it and pasting back on top of itself, and the class name gets a red underscore with the diagnostic "Class '...' already exists in ']]>'".
I have InspectorGroovy installed, so perhaps there's an interaction there.
JVM: Sun 1.6.0_03