Is connecting/binding com port(s) to modem/router, switch possible?

[fbsdmail at dnswatch.com]

Greetings,
 Back in the 3.x days of FreeBSD, if I installed it while my COM ports
were attached to my cablemodem, and switch port(s), a VC was automatically
attached to it. I'm not sure what has changed in that area in the more
recent versions of FBSD, but my previous experiences no longer prevail.
SO, is there any way to achive this same behavior? If not, is there any
way to
achieve a /similar/ behavior? I really miss this. It was /great/ to be able
to switch VC's type in IOS commands into my cablemodem/router. But now I find
myself unable to connect to it, or my switches command port over the
computers
serial port.

Thank you for all your time and consideration.

--Chris