kind of effort required for learning OO perl ?!

Anonymous Monk has asked for the wisdom of the Perl Monks concerning the following question:

Hello Monks, I would like to know what is the kind of Effort required to learn OO Perl. I've expertise in Scripting Perl, i do the following things very well,

basics
regex
all datastructures ( list, hash, nested )
grep, map kind of built ins,
used lot of modules
wrote a couple of modules,

And i have a pretty good experience in IT field, and am a normal learner. Can somebody give me an idea that, how much time/days it would take for me to become expert in OO Perl ?
Also, i have confusion in what is OO perl ? Please what exactly this means ?
Please point me to some document which i can use to learn OOperl from scripting Perl.

Back to Seekers of Perl Wisdom