Form freezes

I have run into a strange thing. We have a customer running 3.70 SQL with clients on Citrix Metaframe. From time to time it happens that a form freezes (often after some period of inactivity i think). It is possible to minimize or restore with the buttons for that, but any content och fields is impossible to access, also not possible to rezise or do anything at all with the form. When this happens all items in the window menu is also disabled. If the user choose to restore the form (with the little restore button up right) it is possible to reach other forms and these are working as normal. After closing down some other forms the one that freezed is back to normal. Any ideas out there?

I have seen this happen on Citrix, where focus gets all screwed up. Not sure what causes it, but you can try Ctrl-Shift or Alt-’-’ to try and get controll of the appropriate window, and bring it in to focus. Worst thing is that some times even closing and restarting the Citrix window does not help.