ownerdrawn Ctabctrl with themes

I use an ownerdrawn Ctabctrl . In the original version, in
CMyTabCtrl::DrawItem ,
there was a
pDC->FillSolidRect(rect, ::GetSysColor(COLOR_BTNFACE));
Later when using themes on Windows XP, I only deleted this line, and everything was fine.
XP has drawn the themed background, and I have drawn the text and the bitmap.
But on vista this seem not to work. Is that a difference between XP and vista, and I have to draw the themed background on vista myself ?

Vista theme (Aero) support does seem to support things a bit differently than XP. I have also had code that worked fine on XP, but, does not work on Vista. I haven't had the time to research it further, so, I've added code that checks for the OS version and reacts differently if Vista is the OS.