Bag of rice
Airing cupboard (or warm, not hot place)
Make sure battery is out and battery cover is off
Leave it alone and forget about it for a few days
If there is ANY moisture visible after this don't try and turn it on, as you have seen the app error you've obviously tried, but everybody does
If you can, strip it, clean it, or take it to someone who can.
Most people will just chance it, but there could still be residue on the board.
The app error needs the software to be completely reloaded.
Use JL Commander, or similar to completely kill/wipe the phone, then after a restart use BlackBerry Desktop Manager to reload the software.
If you get stuck give me a shout.