浏览器中没有显示PHP错误[Ubuntu 10.10]

I'm new to PHP and the whole LAMP stack but I've managed to get it up and running on my Ubuntu 10.10 system. Everything seems to be working with the exception of error reposting in the browser which I just can't seem to get working (and which I can't work without!).I'm new to PHP and the whole LAMP stack but I'v