Chabge admin mail as super admin

Hi all,

I have a MS installation. I make subsites for other people. So when I make these I use a fake mail address. But when I later want to change this mail address to the mail address of the user, the user gets an email then and has to click a link to aprove this change of admin email address on the subsite.

My question: I want to change this mailaddress without some else has te click on a link in an email. Is this possible and how? I can’t find a hook or template tag in The codex whick I could use.