Newbie port conflict

[Marcus Bointon <marcus@synchromedia.co.uk>]

I've got a little circular problem. I have latest PHP port (4.1.2) installed
on 3.1, and also an older MySQL client that it depends upon. If I try to
install an updated MySQL port it complains that there's already one
installed, but if I try to remove it, it complains that PHP depends upon it
so can't be removed. How do I update the existing port?

Thanks,

Marcus