I believe that provided all your keys are in your secret keyring, PGP will automatically pick the correct one for you.
Unfortunately, PGP 2.6.2 will do this only if the PGP message has proper keyIDs. It finds the proper key by matching the keyID in the PGP message to the keyIDs in the secret keyring. If you remove the keyIDs from the message (as stealth does), PGP 2.6.2 cannot find the secret key to use. One fix would be to have PGP (say, PGP3 ;) try all the keys on your secret keyring if the keyID in the message is 0. In other words, you can pseudo-stealth a message by leaving off the keyID and PGP3 would attempt all the secret keys. If one worked, you'd be able to read it. This doesn't solve the whole problem of stealth; you still know that what you have is a PGP message, and even that it is an encrypted message, but you do not know to whom it has been encrypted. The nice thing about this approach is that this works for multiple recipients, too! NOTE: while the PGP3 API should be able to handle this case, I do not know if support for this feature will be implemented in PGP 3.0 -derek