GPG key for release repository?

[gf_gollum]

I'm getting this error when I try to update - I assume that I need a GPG key for the release repository - bbut I'm unable to find it mentioned anywhere. Please can you advise on how to fix this error:-
W: GPG error: http://ppa.launchpad.net karmic Release: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY C18DC20E89617F48

Thanks
Graham

[Stemp]

The key server are overloaded.
It's not very important for now, tomorrow you'll have to type this command :

sudo apt-key adv --recv-keys --keyserver keyserver.ubuntu.com C18DC20E89617F48

[gf_gollum]

Aaahh!.. so the answer was staring me in the face. Looks like the other text is all standard pre-amble - with the key ref. stuck on the end. Fine. I'll remember that for the future. Also - yes it does look like the key server is overloaded :-)
Thx
G.