Menu problems in gtk apps

["Alasdair McAndrew" <amca01 gmail com>]

I'm using Suse 10.0, with kde 3.4 as my desktop.  But I use quite
a few gtk-based apps: firefox, thunderbird, gaim, gqview and so
on.  With each of those I have a problem with the pull-down menus:
the currently selected menu item appears as white text on a very light
grey background - anyway, it's completely unreadable.  How do I
change this behaviour; that is, change menu colors?

I'd be delighted to receive any advice, help or recommendations!

Thanks in advance,
Alasdair