I use a calling card to make international calls on my Treo 600, but it's cumbersome. Can anyone suggest an easy method?

To use my calling card, I only have to dial a local access number and then the international number that I am trying to reach. I have the calling card local access number setup as a speed dial button.

Currently, here are the steps I perform each time I want to make a calling card call: go to phonebook app, look up the number I want to call, copy it, go to speed dial, edit the "calling card" speed dial button, paste the phone number as the extra digits to dial, dial the calling card speed dial button.

There must be an easier way! I don't want to setup speed dial buttons for all international phone numbers in my phone book. If you use a calling card with your Treo, how do you do it??