http://bugs.winehq.org/show_bug.cgi?id=22912
--- Comment #12 from Alexey Loukianov mooroon2@mail.ru 2010-06-22 03:12:01 --- I had successfully tracked this bug down a bit. Looks like this bug is fonts-related and somehow complicated. In case you've got no "Tahoma.ttf" available either fontconfig-wide, Xfs/Xorg-wide and Wine-wide (i.e. inside WINEPREFIX and /usr/share/wine/fonts), and you had provided a reasonable substitute to it using Wine's registry (for example "HKCU\Software\Wine\Fonts\Replacements\Tahoma" = "Liberation Sans") then the rendered font still would be non-ideal, but at least italic subtitles would not be "clipped". I would attach example screenshot I had taken couple minutes ago with wine-1.2-rc4 shortly afterwards.
Removing wine's font replacement and using wine's version of "Tahoma" (i.e. "tahoma.ttf" and "tahomabd.ttf" from "/usr/share/wine/fonts") leads to a problems with font rendering in menus like ones that were attached to this bug in comment #6. Also all subtitles with italicized got clipped on the right side of each letter.
Having original MS version of Tahoma installed either system wide or inside related WINEPREFIX seems to "almost fix" font renderings in menus (there still are some rendering glitches that might be considered bugs), and clipped italic subtitles also present.
No matter which version of "Tahoma" is used adding wine font replacement like "HKCU\Software\Wine\Fonts\Replacements\Tahoma" = "Liberation Sans" fixes the displaying of italic subtitles (as shown at attached screenshot). Still the font seems to be cripped (what had happend to the font smoothing?) and I doubt if it is rendered with the correct color.
Inspecting the contents of the "HKCU\Software\Wine\Fonts\External Fonts" registry key shows that the original Tahoma font haven't got pre-cooked TTF files for both "Italic" and "Bold Italic" (tahomai.ttf and tahomabi.ttf) and it looks like this is the key point that triggers this bug. Having replacement font defined for Tahoma makes wine use tahoma.ttf/tahomabd.ttf for Regular/Bold Tahoma, while using LiberationSans-BoldItalic.ttf/LiberationSans-Italic.ttf replacements for "Bold Italic"/"Italic" Tahoma.