Grip will compile fine against gtk+2.3.1, yet the ebuild blocks it, saying it needs the 2.2 branch. I compiled it today, and it runs fine. Reproducible: Always Steps to Reproduce:
There is no gtk+-2.3.1 in portage. To keep people's systems sane we lock it to the 2.2 series... the 2.3 series is considered unstable and as gtk+ is such a core component of so many people's systems, we try to keep control of it... The "unstable" version of gtk+ WILL be incompatible with other programs, no doubt. It's good to know that you have found no problems with grip though. :)
But there are no other packages that state they need gtk equal to a version number, (that I have found). For at least concistancy reasons, it should be changed.
modified the 3.1.3 and the 3.1.4 build.