Telneting from Windows Vista hungs after typing some chars

I tried to use the telnet utility to connect to a different devices that can
be managed by telnet (ie: router, AP's, switches, etc.). I have the response
from the remote host that I'm telneting, baut after typing user and password,
no other commands can be typed. If in the same Pc I boot with Windows XP Pro
and use telnet i can success login, and type commands. This is a extrange
behaviour. Does anyone observed this?

PS: I tried with different telnet clients form Vista like native telnet.exe,
hyperterminal, Putty, etc., and all telnet clients hungs after a few comand
are typed.

Any ideas?

Thank you beforhand.

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