CTRL-F6 (toggle between windows in MDI) fails

[EiSl]

Hello all, After almost completion of my MDI appl, I figure out that the hot-key CTRL-F6 (switching between windows) is not working anymore (might never have worked :-D ). I haven't change anything in the accelerator resources (it's actually still there). In a default MDI-project of VC++6.0 it does work. It might have something to do with having a tab-control bar I've included (as part of MainFrm). The doc/view are also splitted, but that should be at another level. Have any of you any idea's how I can pin-point where it's going wrong? By the way: what messages are sent? Thanks in advance, EiSl