Sorry to repost, this ended up in wrong forum originally!

'm considering building an application which will send SMS text messages from an email. For example someone could send to

[email protected]

I also need to recieve normal smtp email through the same connection which this application would use.

So i'm thinking something like this would work.

1. My application listens on port 25 for all incoming messages
2. When message comes in it checks for "sms" in the to address. If its there it processes the sms message
3. If not then it assumes its a normal smtp message and relays to the mail server which will listen on port 26

I understand how I want it to work, I just wondered if anyone had any experience with the SMTP protocol, is it easy to implement. All i'll need to do is read the TO: addresss and then, worst case scenario relay the orginal message on.

Thanks