When I ran
(echo "something"; cat some_file) | telnet some_host
I've got (after some time):
telnet: buffer overflow, losing data, sorry
telnet: ring.cc:132: int ringbuf::flush(): Assertion
Abort (core dumped)
some_file has a line about 400Kb long.
The bug is 100% reproducable
I run RedHat 5.1 + all updates.
Fixed (by scrapping th C++ telnet client in favor of the OpenBSD
client) in telnet-0.10-25.