Finish the patch in bug 623278 and attach it in the bug.
To accomplish this task it will be needed to build pygobject and all the required libs using jhbuild. You can find information about how to do this here. It is an advantage if you have already used jhbuild before.
To build pygobject use the command "jhbuild build pygobject".
In case you have any problems and you need a quick answer you can find us in the #python channel of GimpNet IRC