SQL 2005 - SQLDMO - Adding Logins/ Users

I do not understand the sequence in which to add logins/users. A couple
of things to note. I can not use vbscript - it has to be done using the
sqldmo objects (or in a sql script).

The sequence I use now is:

1- create login, set default db
2- add login to sql server
3- set db owner
4- create user
5- add user to master db
6- add user to tempdb - blows up here
Error 'Microsoft SQL-DMO: [SQL-DMO]This object is already in a
collection.'

I need the user in 3 dbs. Any help greatly appreciated. Thinking about
it...I bet by adding it to the master db that it is automatically added
to tempdb so I will try to add it to the 2rd db and see if that works.

Thanks!
-Will