Memory limit reached but no error displayed

Hi, I have found a bug in one of my scripts. It doesn't output anything, just a 100% blank page. I debugged it to a single implode line. If I comment it, it's ok, the page show my debug echo's and stuff, if i let the script run that line the result is a blank page even with echo's done before that line. I think the problem is memory limit, when i change it to 16M it works fine. But my doubt/problem is about error reporting. Shouldn't it appear something saying: memory error or something? It doesn't appear anything... I have error_reporting E_ALL, maybe I should look to other config's? which ones? Thanks in advance for your help, Paulo JF Silva