How to Install Openfire Latest Version for Centos 5.6 (final) 32 bit

I have machine running Centos 5.6 (final) 32 bit. I tried installing openfire 3.6 version. I am unable to login as administrator (admin) even after looking at actual openfire database ofUser. I tried multiple times with false in openfire.xml. I read some where there is a bug on the system with initial login.

  1. What is the latest openfire version I can install on Centos 5.6 (final)?

  2. What are mysql and java version needed?

  3. Any good php wrappers to add remove users, groups, roster? What is difference between a group and roster for individual user? I read some where using plugin is prefered instead of directly adding the mysql tables is not a good idea due to Openfire user list in RAM and does not load users until service restarts.