I just did it again last night during testing of the new SME 5.
the password is in /root/.my.cnf
#cat /root/.my.cnf
look under the [client] section and you will find something like this
[client]
password=xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
be careful of line wrapping. there is only one line under the client section. if it wraps on you, you may be missing some of the password and that will be your problem.
J-L