Here, the customized firefox means that it is not the distribution package, but the self-downloaded and static firefox.
download
jdk from http://www.java.com/en/
[SU]
[] mv jdk-6u18-linux-i586.bin /home/softwares/[] cd /home/softwares/[] sh jdk-6u18-linux-i586.bin [] ln -s /home/softwares/jdk1.6.0_18 /opt/jdk[USER]
[] cd .mozilla/plugins/[] ln -s /opt/jdk/jre/lib/i386/libnpjp2.so libnpjp2.sorestart the firefox.
reference
http://java.sun.com/javase/6/webnotes/install/jre/manual-plugin-install-linux.html