Postfix - Can't recieve from own isp

hello, I am having trouble recireving mail with postfix from my isp. Postfix seems to be running great, I can send/recieve from hotmail, shaw etc. but my isp bell, I can't seem to get any mail. I can send ok.

The log file show repeatedly:

postfix/smtpd[5841]: timeout after DATA from simmts10.bellnexxia.net[206.47.199.77]
postfix/smtpd[5841]: disconnect from simmts10.bellnexxia.net[206.47.199.77]
postfix/cleanup[5844]: 48E5E280C3: message-id=<002201c4e7d8$17bd7160$6c35fea9@gb001>
postfix/smtpd[5848]: timeout after DATA from simmts12.bellnexxia.net[206.47.199.141]
postfix/smtpd[5848]: disconnect from simmts12.bellnexxia.net[206.47.199.141]
postfix/cleanup[5849]: 662B5280C4: message-id=<000601c4e3c3$2abb91c0$6c35fea9@gb001>

This occurs about half hour +/-. Any idea whats "@gb001" ??
Is there some configuration I can change to recieve mail from in my isp.

Thanks for any help.

Mandrake 10, Postfix