There are a few changes in glibc-2.10 that might make your software fail to build with it, please refer to my blog post  if you're not sure what the problem is.
And no I don't usually provide emerge --info with these bugs because they are caused by glibc-2.10!
Created attachment 196346 [details]
Created attachment 196357 [details, diff]
patch to fix compilation with glibc-2.10
This patch should fix the failure. I can't test it though, since I don't have gcc-4.4. Maybe someone could send it upstream too?
ps: Davide, I commited my patch before looking into this bug. Seems like our patches are 100% identical :)
Are you willing to send this patch upstream or I will do it later :)
Let me know
I'll let you do that, I'm lazy ;-)