java plugin for mozilla; mozilla crashes

[george <golfone@tin.it>]

Hi I have a problem with the java plugin in mozilla: I installed the sun 
jvm 1.4.1; copied the java plugin for ns610 in the appropriate mozilla 
plugin directory; when I look at the plugin info page of mozilla the 
usual list of java plugin capabilities, just like it worked. But as I 
open a web site with any java application mozilla self shuts down. I 
can't understand why...
Anyone knows what I can do?
I am running debian  sid, mozilla 1.1
Thanks

Marco Giorgetta