Exec() problem

I need to call exec(/usr/sbin/adduser -g pppusers -d /home/tester -s /sbin/nologin -p test tester) from my php page, but it doesn’t seem to work, and since addusers doesn’t give an output, there’s no real way of me debugging this. I’m thinking it’s the call\perameters, but not sure. Basically, I need the page to add the user to the system with the perameters. If anyone knows of a better way, then I’d love to know. BTW, yes, I am 100% I want to add the users to my /etc/passwd and /etc/shadow files in my server, I am aware of the risks this could pose…

Thank you

shell_exec() to get an output !

prolly that apache doesnt have the rights to do so… but never know