I see! I checked out that thread and they identify something I've noticed too.
When you lose the dial-up connection and re-dial, the publishing rules don't seem to activate. If you check the Alerts node, you'll notice an error that says something about a resource allocation failure, and you'll see a little bit later that there has been a failure in a server publishing rule.
Why does this happen? Don't know - probably will be fixed in ISA Server SP1.
However, you can kick start the rule by disabling it and then re-enabling it.
If you get SMTP and POP3 publishing failures when the connection has *not* been dropped, try disabling the POP3 and SMTP filters.
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