[Evolution] Error from gpg - key requires a 256 bit or larger hash

[b1 <forum b1online de>]

Hello alltogether

I have, or at least I think I have configured PGP-Encryption in
Evolution. 
When I try to send a signed E-Mail, I get prompted for the passphrase.
After entering the correct passphrase I however get an error from pgp:

Could not create message:
because "gpg: writing to `-'
gpg: DSA key 0114C5B2 requires a 256 bit or larger hash
gpg: signing failed: general error
", you may need to select different mail options

I have absolutly no idea, of what to do now. I am using Evolution
2.28.3.1 and gpg (GnuPG) 1.4.10.

It would be really great if someone of you has some suggestions. 

Thanks in advance

B Brandt