Or an easier solution is to use a "smart host" which is your ISP's mail 
server acting as a forwarder when you're sending mail. The same mail 
server you use to send mail for your ISP e-mail account should work.

Brian D. Ropers-Huilman wrote:
> On 4/3/07, Jon Schewe <jpschewe at mtu.net> wrote:
>   
>> Has anyone else run across this?  As of today I'm no longer able to send
>> mail through my mailserver (mtu.net) port 25 as comcast is blocking all
>> outgoing connections on port 25 for "my protection".
>>     
>
> This is a fairly common practice to prevent you from using mail
> servers that are not their own. One easy solution is to setup your MTA
> to listen on another port (I've used 2525) or to send via SSL/TLS as
> they never think to block 465.
>
>