[Serusers] Can't create ser user

I'm trying to build the tables needed for ser in mysql, through the ser_mysql.sh script. This script asks me for a passwd, after the passwd, he gives the following error:

ERROR 1007 (HY000) at line 1: Can't create database 'ser'; database exists.

I'm entering the ser user passwd but i can't get it to work. I tried to create the user ser at mysql with the following command

mysql> create user ser password mvx

But it gives the following error:

ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'user ser password mvx' at line 1

I'm using mysql version 4.1.7 ...

What am I doing wrong ?