Java plugin problem with firefox

[Richard Tobin]

I just built and installed the firefox-0.9 port.  But when I try to
run it I get endless repeated messages:

LoadPlugin: failed to initialize shared library /usr/local/jdk1.3.1/jre/plugin/i386/ns600/libjavaplugin_oji.so [/usr/local/jdk1.3.1/jre/plugin/i386/ns600/libjavaplugin_oji.so: Undefined symbol "_vt$16nsQueryInterface"]
*** loading the extensions datasource

My jdk1.3.1 is jdk-1.3.1p9_4, and it works with the (old!) Mozilla 1.1
that I have installed.

Can anyone tell me what the problem is?  Do I need to install a newer
jdk?

-- Richard