mdi.c/MDI_ChildActivate query

[Jeremy White]

Hi,

When trying to run 'Swiss Perfect' (www.swissperfect.com,
free download available), the app crashes and burns while
processing a WM_MDIACTIVATE message when the prevWnd is 0.

If I modify the code as in the attached patch, everything works.

I can't determine if the app is flawed or if this is a good
change to Wine; I'm hoping an MDI expert can kibitz.

Cheers,

Jeremy