I've never played with echo link, not even sure what it is. hi hi.
Anyhow, I had a similar problem with ventrilo (a chat program), and
letting my ham friend access my router and system.  I'm on dsl and with
sprint.  What was happening here is the modem had a fire wall and was
doing network address translation and the linksys router was as well.  I
called tech support and they had me do a reset and set the modem up as a
bridge only.  No login from the modem, and no n a t.  All that is done in
the router.
73s
Butch Bussen
wa0vjr