Does MWM_DECOR_BORDER really cause window to have caption?

[Kirill K. Smirnov]

Hi,
I'm trying to get winamp playlist window to be painted correctly (bug #8300).
The problem is:
0) wine version is git-current.
1) winamp playlist window style is WS_CLIPSIBLINGS
2) winex11 driver converts it to MWM_DECOR_BORDER hint. (window.c:599)
3) This hint behaviour is WM-dependent:
  a) KDE - caption is painted;
  b) XFCE - ditto;
  c) fluxbox - correct (no caption).

This situation confuses a little. I believe DECOR_BORDER does not add a 
caption to window, but it does under great WM such as KDE. Is this behaviour 
correct? If KDE/XFCE is a culprit, should we add a workaround into wine?

Thanks for attention
--
Kirill