(using squirrelmail 1.4.0, server/php/imap irrelevant;
I couldn't find another bug dealing with this)
And you've got yourself a busy loop (the while will be
executed everytime with $pos remaining 1 and $j
Though 'a<b' in syntactically incorrect for an
emailadress, parseAddress shouldn't be busylooping on it.
This error is still inside 1.142 of imap_general.php
(the current HEAD)
In order to provably prevent a busy loop, $pos - $j
should always be increasing, whatever happens inside
This is ensured in most switch-cases, only in the '<'
case there is neither an increasing $pos, nor an
decreasing $j. In the ':'-case it's not easy to check
because of the recursive call, but it looks okay.