ERROR: user "test1" is not allowed to create/destroy databases

hi all

I have following commands:

$psql mydb
mydb=> create user user1 createdb;
mydb=> \q

$psql mydb -u
username: user1
mydb=> create database dbuser1;
ERROR: user "test1" is not allowed to create/destroy databases

I don't know why this error happen :(

Stanimir