When I want to email a coupon to a specific customer, it takes forever to load the email screen where I select to whom the coupon is to be emailed to. I do have a large customer base, but it doesn't take this long to open any of the other customer screens.

What would cause this? I literally open the coupon admin, click the email button and go do something else while waiting for the screen to load. At first I thought it was broken.

Version - 1.3.8a and PHP5/MySql5 server running Apache - This is a stand alone server with only this site loaded on the server, so its not a server busy issue. All resources available to this site.

Thanks in advance.