How to reproduce:
1) Open the above URL
2) Click the button
3) See mozilla crash

Reproduceability:
always

Notes:
This is the same complaint as mozilla.org bug #89536
(see http://bugzilla.mozilla.org/show_bug.cgi?id=89536 for more info)

The fix for this has been checked into the trunkm and should be in 0.9.3,
and it has been checked into the branch for 0.9.2 post mozilla.org release. 

Suggested fix:
Update to the 0.9.2 branch at the Netscape61_RELEASE tag or update to 0.9.3