It sounds like you are looking for SubEthaEdit. It is directly made
for remote pair programming. See here:
http://www.codingmonkeys.de/subethaedit/collaborate.html
--
Sven Axelsson
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>++++<<<<<-]>++++.+.++++.>+++++.>+.<<-.>>+.>++++.<<.
+++.>-.<<++.>>----.<++.>>>++++++.<<<<.>>++++.<----.