MYSQL server stops when i log in to wordpress admin pages

Hi

I have a web site, on a remote Linux server with 2 databases already installed to administer a members area.

I have just installed wordpress. The installation seemed to go okay and i could view the default blog page, however, when i tried to login to the admin pages i got a database connection error. I then found that all database functions on the server had stopped working including the existing 2 databases. The reason was that the mysql server had stopped. I restarted and everything was fine until i tried to log in to the wordpress admin pages again.

Every time i try to log in my mysql server gets stopped.
Any ideas why this is.

thank you