Don't you need to supply the password for MySql's root user too?
You can also add "-D database_name" to directly start using one of the databases.
Furthermore, I think your syntax in
mysqladmin -u root password 'pass'
is incorrect too.
You're supposed to use either:
or -p 'some_passwd'
where you need to replace 'some_passwd' with the actual password, of course.
Don't mix the 2 syntaxes, otherwise it may still work, but it won't do what you are trying to accomplish.