[CentOS] Installing skype in CentOS 5

Having just upgraded my system from CentOS 4.4 to 5.0, I'm a bit
disappointed that I still can't install skype from the skype repo using
yum - when I try yum install skype, I end up with:

libsigc++20-2.0.17-1.el5. 100% |=========================| 217 kB
00:13     
---> Package libsigc++20.i386 0:2.0.17-1.el5.rf set to be updated
--> Running transaction check
--> Processing Dependency: qt4-x11 >= 4.2 for package: skype
--> Finished Dependency Resolution
Error: Missing Dependency: qt4-x11 >= 4.2 is needed by package skype

Any ideas please as to how this can be overcome so that I can install
and run this very useful utility?

Andy