pgp and gnupg at the same time?

[Mipam]

Hi FOlks,

I noticed gnupg and pgp5 are not compatible.
I cannot open mails encrypted with gnupg.
Is it possible to use gnupg and pgp5 at the same time with mutt?
I doubt it cause how would it know with to use for a message.
It's reall not nice that its not compatible....
Any suggsestions? cause i really would like to encrypt messages
to gnu and pgp user both.
Bye,

Mipam