Public bug reported:
Binary package hint: xchat-gnome
see here: http://img247.imageshack.us/img247/8127/xchatmb5.png
it is really not compliant with a transparent panel.
** Affects: xchat-gnome (Ubuntu)
Importance: Untriaged
Status: Unconfirmed
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systray background is gray
https://launchpad.net/bugs/61115