Security Software

Hi,
I'm a newbies in Oracle Identity, recently I have join a company where they require me to pick up the Oracle Identity manager fast so that I could replace the role of the resigned staff. I have few question in mind:

1) In oracle url I see the Oracle Identity management latest release is 10.1.4.0.1, but my company is using Oracle Identity manager 9.0.1, are we having the older release of Oracle Identity (but according to the resigned staff we have implemented it since the beginning of the year)?

2) We are using Jboss as our application server, I just wondering why we are not using Oracle application server instead, is that a must to have Jboss as the application server in Oracle Identity manager?

3) Apart of this, we also running Novell identity manager, why do we need Novell identity manager?

Appreciate if anyone can give me bit of clues how to relate all this (even if it not the actual environment setup but at least I have the brief possibilities of thought)?

Thanks

best regards,
chong