[otrs] Postgres problem

hello all i am using redhat 9 .. i was just wondering if i can use postgres instead of mysql working ? if anyone has instructions on how to do that i would be very grate full... i got all of otr's working on my sql and apache on redhat but my manager if very picky and wants to use postgres instead of mysql database..... anyways if you can help me out with step by step con fig i would be realy great fully.