Help Needed

hey guys whats`up

i just installed openfire 3.7 on my linux centos server

and now am working on my xmpp client

but i am facing some problems and i have some questions !!

1/the clustring is not working am using Mysql Database

it gives me an Error

java.lang.NoClassDefFoundError: com/tangosol/net/Invocable

at java.lang.Class.forName0(Native Method)

at java.lang.Class.forName(Unknown Source)

at org.jivesoftware.util.cache.CacheFactory.getMaxClusterNodes(CacheFactory.java:4 80)

at org.jivesoftware.util.cache.CacheFactory.isClu…

2/ my chat application should be able to support upto 500k users !

how can i handle that !

what changes should i apply on my server …?

i read about connection manager ! but i didn`t understand how to use it or how to install it

please if any one can help me or give me tips

i will be so gratefull

yours

sherif

and also i read about network load balancing !! i didn`t understand it tooo …