[NTLUG:Discuss] How to avoid mail loops?

[Neil Aggarwal]

Hey all:

I am working on an email service where users can forward
their incoming email to another email address.

I just realized that this can easily lead to a mail loop
and consume all of the resources of the smtp server if that
email account forwards the mail back to the email account
it came from.

I have considered marking the messages with a header somehow,
but that depends on the remote server giving me back that
header.  If it doesn't I have no way to detect the loop.

Any ideas how to avoid this problem?

Thanks,
	Neil

--
Neil Aggarwal, JAMM Consulting, (972)612-6056, www.JAMMConsulting.com
FREE! Valuable info on how your business can reduce operating costs by 
17% or more in 6 months or less! => http://newsletter.JAMMConsulting.com