i was investigating this 'issue' this weekend. crawling the code is one thing, play testing another...
i did a play test from 8pm to about 2am 5 boxing across 2 machines, one xp... one vista.
no disconnects at any time (although i did get wiped once in rfc... i was getting tired and my lowbie rogues need better gear)

i will continue to look for this issue, but it is difficult if i cannot reproduce.