poor HTML syntax crashing (!) netscape

Hi guys, I have an interesting situation at the moment... my (slightly sloppy) HTML is obviously missing a closing tag here or there but displays fine in opera, ie etc however when I try and view it netscape (4.x, windows, linux, any platform) netscape just nice and cleanly crashes!! If anyone knows of a bug which would cause netscape to do this then please let me know. The code in question is very dynamic (what I mean is that it can vary by quite a lot depending upon many many different things). Its qutie hard to debug, especially seeing as the page returned is browser specific.. the one thing I have ruled out is that it is JavaScript.. I removed all of that and no change. Any tips will be helpful... in the meanwhile I'm going to go thru all my functions to attempt to work out what is doing it.... *yawn* TIA Tom.