Joe Lowery on "WP not seeing current PHP version and preventing upgrade"

I have a client on Yahoo!@ Small Business web hosting who recently got hacked. I tried to upgrade to the latest version of WP, I got this error message:

You cannot update because WordPress 3.6.1 requires MySQL version 5.0 or higher. You are running version 4.1.14.

I moved the site to a more recent PHP version and confirmed through phpinfo() that MySQL is now at 5.1.55; PHP is 5.3.6.

I logged out of WP and logged back in but the error message remains. How do I get WP to recognize the current MySQL version and permit the WP upgrade?

Thanks - Joe