Strange mail problem

Hi, in order to use mail function from my script in local mode (php3 e php4 on win box with apache), I take a strange problem ... I mean, if I use a simple mail function on a script parsed by php4 all works fine: instead, using the same function on a script parsed by php3, my system box crash and do nothing ... In php*.ini there is "the same" configuration for the mail function in a win box, and I don't think that the problem is due to my code (as you can see): <html> mail("me@me.com","hello","this was send by local php machine"); </html> Anyone could suggest me where I can take a look to solve this problem? Many thanks in advance max