ok guys ... I'm pretty desperate right now ...
what I did was I updated to the latest SW package UC520 8.0(1) using the latest version of CCA (2.2 I guess).
I left the config alone (I have a pre-upgrade copy of my startup-config as well).
after reloading the UC520 all of our phones are dead (most of them being SPA525Gs). they all hang at "connecting...".
sigh ... any ideas guys?
Only other thing that I see in the posted config...
You don't have a load statement for the 525 and you don't have a tftp server command statement for that load.
But, the other phones that you have should have come up. I can help you look at the differences in the configs to see if that helps.