sqlippool duplicated IP assignments

Hi everyone, I'm using freeradius-2.1.12_1 with MySQL 5.1 and sqlippool configured to assign IP's to my PPPoE clients, I redistribute these routes with iBGP, until yesterday it was working fine, the problem started after a blackout that happened last night. I have a lot of clients that are being assigned duplicated IP addresses and I just don't know why, I've configured a long lease time for each assignment so that the NAS has a good time frame to transmit the interim updates, my radippool table is using the engine InnoDB and I think the select lock should be working fine. Any suggestions?