Adding users...

[Xpression]

Hi list, I installed Apache and ProFTPd servers, users can
upload tehir sites via FTP, I have configured in Apache
DocumentRoot in /usr/local/apache2/wwwroot, my question is:
can I create users which their home directories path is
/usr/local/apache2/wwwroot/userN ??? Is this way trustable
??? I was thinking it because if it's no possible I have to
change my DocumentRoot wherever the main site is
located...thanks...