after upgrading to 13.10 Enigmail refuses to work. I can't decrypt older messages nor encrypt new ones. GPG is working since I can encrypt text from the CLI. For example
echo "Test" | gpg -s

The OpenPGP-Debug-Log says it can not find my private key. But I did not change anything compared to 13.04. I tried deactivating every single addon, including Enigmail, since I found this hint on another forum. But it did not work. When I try to decrypt a message there's an OpenPGP dialog saying: Error - Verification of signature failed (translated from german). I can't even decrypt my own emails that were encrypted by my private key, too. Any idea what's going wrong here?

Kind regards