My best guess jim is that this would be for an outbound connection from your IE. I'm not really an IE/browser guru actually, to actually break down and disect it. I think you should be safe tho. What other services are you running on that rig? any DNS, or iss, VisualStudio or such?
These ports have been in use for quite some time now Jim, just may not have recognized it beforehand.
If you want an in depth detailed write up on telnet com port control ... source: RFC 2217 (rfc2217) - Telnet Com Port Control Option
This article goes waaaaay back to 97.
mod may want to move this to security instead of networking.