Nige its the port *most* pop3 mail servers use. AOL doesnt like people being able to use POP3 mail (even if it aint to their servers, but to another mail server), so randomly block it. So sometimes, you try to send an email and itll fail and fail and fail then work fine the following day

Ive not found a way to unblock it propperly as its on AOLs servers i think