pop3 proxing!!

hello, i'm in need of help i'm using suse 9.0. I want do foward pop3 from my intranet into the external mail server(isp), but i'm not having any luck in doing so, i have susefirewal2 activated and the proxy in yast activated. for http i'm using squid and for ftp i'm using proxy-suite from suse. i would like to let my intranet to see ther mail form the isp server. thank you for any help that can came from anyone on this list!