Pulling my hair out over Netscape...

Hello everyone... I've been developing a PHP app here for a while now, and I have been encountering some most frustrating situations in which something will work in IE but not Netscape. Some of this seems to be IE's allowances for sloppy coding... :) But here's a new one. I have a form, that if you were to submit this form once, it will always retain the same value. I.E. I enter a value, hit OK. Then I press the back button. Then I enter a DIFFERENT value, and hit OK. The SAME value is passed to the PHP script! I'm using the post method, and I haven't found a way to shake this yet! This is afflicting Netscape 4.7 and Netscape 6. Driving me crazy.... Thanks in advance, Michael