resolves the following error when starting Mozilla:
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 "XtShellStrings"]
While I'm here add a tweak to prune empty directories before installing
JDK, so that JDK installed from a pre-built package deinstalls properly.
Bump PORTREVISION.