Install new version of Qt/Qt-Creator on 11.4

I am using openSUSE 11.4 with KDE 4.6 that uses qt 4.7.1. I would like to upgrade the version of qt-creator from the standard 2.1 to the current 2.5 but that requires also to install qt 4.8 on top (or apart from) the system’s version. There will be some problem on doing that?

Another question: Which repository should I use to get an updated but stable version of qt-creator? The OSS repository does not have any updated version but there are lots of packages in software.opensuse.org: Download openSUSE 12.1 under “unstable packages”. Or may be downloading directly from Nokia page?

I know there is a list of qt repositories here but I have never used them. KDE repositories - openSUSE

I am unsure about qt creator.