In gentoo-sources, "make xconfig" doesn't work with qt4 as qconf is written for qt3. I managed to convert it to qt4. Patch attached. Beware: These changes probably aren't the best way of doing this. But it seems to work
Created attachment 232265 [details, diff] Changes to allow qconf to work with qt4
This is really a duplicate of bug 133751 but since you have a patch attached, I'll reassing this to gentoo-sources maintainers for review.
Frankly, I wouldn't call anything that still uses Qt3Support as a port - it was meant only to make the initial porting easier, but that long since qt4 release, it should not be needed.
I'm ok with this patch until someone provides a better port. I think user's want this functionality and it won't affect the usability of ones system but provide a convenience for people that like xconfig. This will be in the next gentoo-sources 2.6.34. If someone is dying for this is 2.6.33, let me know.
Did you send this patch upstream? Looks ok to me
Released in gentoo-sources-2.6.34-r1