How do you get iphoto to print custom sizes?

[JellyFish]

I need to print a 2.5 x 3.5 photo but iphoto will only do 2 x 3.

How can I print a custom size? I have iphoto 6. I cannot seem to find a way.

Am I missing something?

JellyFish
The iPhoto Newbie

 

[JellyFish]

BTW, I used Seashore to sort of get the size. But it's still not quite right.

I wish iphoto could do this...