Custom page setup in pages keeps asking for cm. I need inches.

I don't know what else to do. I've got my document ruler set up for inches, it even says 8.5 x 11 inches in inspector. But when I go to page setup >> manage custom sizes, it's preset to cm.

Where do I change it so the "page setup" thingy will ask for inches?

Thanks.

NM, figured it out: preferences >> Language and text >> Format >> US

Glad you figured it out.
Also thanks for posting the solution for future people who search for this!