How the change the Pricing in Membership?

Dear all

I am using the dolphi 6.1, and i want the user pay for my website by minute not by day, how can i do this?

Following is the "Manage Membership Types" i want to calculate by minutes.  which flie, where i can modify?

Regards

inc/membership_levels.inc.php

function setMembership

replace:

$dateExpires = (int)$dateStarts + $days * $SECONDS_IN_DAY;

with:

$dateExpires = (int)$dateStarts + $days * 60;

every integer now will = 1 minute not day

change all your day strings to minute

have fun

thanks very much, i am realy appreciate your reply,