Unknown signature keys

Hi

I just installed openSUSE 11.2. When I tried to install the Multimedia Codecs and the NVIDIA driver I was presented a lot of complaints about unknown keys. I tried to look up a few on MIT PGP Key Server and on DFN-CERT: PGP-Keyserver but could not find them.
Examples are F5113243C66B6EAE or B2F796E76867F5BE

Is this normal? Does anyone know if the keys are trustworthy?

Many thanks for a quick answer
Martin

Just accept them.

Thank you, that’s what I am going to do. But I still feel that this against the security level necessary today.

Regards
Martin