[HM] Treo and dot Mac

[Johns Maillist]

I am not sure where to take this question, so I will cross post it, I  
am sorry if this is an issue with anyone.

I have a Treo 650, and have been trying to get it to work with my dot  
mac account.
I have Cingular, and  It receives from my .mac server, no worries.
The sending is the issue.
Does anyone know the settings for using my Treo with this set-up.
Thanks, John