Hm, there never was a PyQt4.6.2 version outside of extras-devel. Currently, there is a single version out there (4.7-maemo7), which is in Extras proper. The proposed upgrade path is correct, the question is what is holding back the actual upgrade. It must be something version-specific as 'apt-get install barriosquare' does the upgrade properly on my test rig. Did they install PyQt manually perhaps, via apt-get install ? The Hildon App Manager is very conservative in that regard, IIRC it will rather say problems instead of updating something not initially installed by it...

Alternatively, if apt-getting new versions doesn't work out, I suggest they uninstall the PyQt version they have, as that is a really ancient (so ancient that it has been erased from extras-devel), and install barriosquare anew.