ECO error: Incremental compilation off?

Hi

I'm still having troubles with ECOs in Quartus 9.1. When I try to commit some ECOs, the fitter complains:

Error: Run Analysis and Synthesis (quartus_map) with Incremental Compilation enabled for top-level entity name "titlis" before running fitter (quartus_fit)

Now, incremental compilation is at its default value, what is supposed to be enabled (the corresponding dialog entry says "Full Incremental Compilation").

This seems somewhat contradictory to me. Do I have to enable something special to keep this working?

Thanks and best regards,

emanuel