hm thats funny I didnt know there was a code that said the o2 sensors were bad?(sarcasm) My first question would be did the code say the o2 sensor were reading rich or lean. next question would be did you check the ground from the computer for the o2 sensors. third question is do you have any exaust leaks. if you have an exaust leak on the collector it can cause the o2 sensor to read a continuous lean condition (no mater how many times you replace them)
Don't make the assumption some people make that a code means a bad part. a code just leads you to the problem.