Freeze/Deadlock when showing a tooltip

This occurred so far with the installed Creator and Qt from http://releases.qt-project.org/digia/5.0.0_rc1/backups/2012-12-05-365/qt-linux-opensource-5.0.0-rc1-x86_64-offline-2012-12-05-365.run

I can't reproduce this reliably.

So far it happened twice in the debug mode of Qt Creator. Looking into the backtrace it seems to occur on a mouse over of an item view. This tries to display the tooltip and hangs somehwere at pthread_cond_wait.

I've tried to mouse over all items in all item views in the debug mode several times but couldn't reproduce this.