And now I again removed kernel-PAE-2.6.33-0.52.rc8.git6.fc13.i686 and booted kernel-PAE-2.6.33-1.fc13.i686 and dialup networking still works. So apparently there was some transient problem the first time I installed kernel-PAE-2.6.33-1.fc13.i686 and removed kernel-PAE-2.6.33-0.52.rc8.git6.fc13.i686
Sorry for the false alarm - but it really did fail the first time I came up on the new kernel.