phpmyadmin outside plesk, how to?

[alli81]

Hi, i have a little problem (sorry for my english)
I have phpmyadmin inside plesk and is ok for me, but now i must give access to phpmyadmin to another person but i don't want i come in plesk.
How can i do?
Is possible to make something in automatic for have phpmyadmin in an url like: www.mydomain.it/mysql ??
Can you help me?

P.S. i try to install another package of phpmyadmin in the root of 1 my website, but if i try to make login i have this error:
#1045 Impossibile eseguire il login nel server MySQL

in english:
#1045 is not possible to make login in the server MySQL...