Hi,
I'm having exactly the same probelm as you, SP1 applied (with elevated permissions, just a bad force-of habit I guess), applied all 4 pre-requisites and everything installed nicely.
When I try and access OWA, I can read emails fine, but as with you, I can't delete them, change settings and a few other things.
Perhaps this'll teach me to not apply patches into production on the day of release. Grr!!