How do pop3-read messages get "marked"?

Hello all,

I am reading my Domino hosted mail either through my Notes client or through my Palm in POP3.

My problem is that my Palm does not recognize docs that I have read with Notes as “read”, therefore trying to download all of them. It does recognize those it has already downloaded though.

I have looked in the Notes docs if there is a difference between a doc that has been downloaded in POP3 and one that has not, but I don’t see any difference.

Do you know how the POP3 client recognizes e-mail it has already downloaded?

Thanks