icewm titlebar gradients not displaying properly?

[pizza-rat]

I'm using a Win2k theme on icewm and the titlebar gradients are rather blocky. I can take a picture if needed but basically the gradient is in ~30pixelish chunks per tone instead of a smooth transition. The screenshot for the theme (and other similar themes which have the same issue) show the gradient displaying as it should.

For useflags on icewm I have alsa, gdk-pixbuf, imlib, nls, truetype, xinerama enabled. ao, bidi and debug are disabled.

Any ideas what's causing this?