I also tried the php upgrade script. As Greg pointed out, the unixODBC rpm will never be installed. As we like all rpm files in the temporary 'phpupgrade' subdir to be installed, 'rpm -Uvh --nodeps php*.rpm' could be changed to 'rpm -Uvh --nodeps *.rpm' and that should do the job.
Here the link to the unixODBC rpm seems to work fine...
And so far all my PHP applications seem to work fine, so thanks for the efforts!