Java plugin malfunctions

[Yuri]

Hi,

I am looking at: http://websdr.sp3pgx.uz.zgora.pl:8901 This is web ham 
radiostation.
It works the first time you open it. But when I click on "all bands" 
then "one band" and like this few times page hangs.
It also doesn't show up again when I close the page and reopen it again. 
Killing java process doesn't help.

15.0.874.121 (Developer Build 0 FreeBSD)
Java installed according to the handbook: openjdk6-b23_1 + 
icedtea-web-1.1.4 + symbolic link.

Same works in firefox fine.

Yuri