Open up synaptic package manager and look at the following programs:
"packit", "ser2net", "cereal" "vtun"

I don't know if any of these are quite what you want, but their description
seems to be related to what you want. I just opened up synaptic manager and
searcher for serial to ip... my appologies if you have already done that and
didn't find anything useful there.


Also, Does one of these not do what you want?

http://www.tibbo.com/downloads/soi.html
linux.softpedia.com/.../SerialOverIP-14322.shtml

Not coming from the repositories, or course, there is no way to say w/o
looking at the code what the integrity of the products/sites are. But may
be worth looking into?