I had a problem with this contrib, and translating the title.

It acts independently of the Drupal language system because it replaces the Shipping title with it's own, through Javascript.

I just commented out the part in the contrib that changes the title... now the regular Drupal shipping title is back, and translateable. GREAT!

uc_autocalc_shipping.module

$("#quotes-pane legend a").text("Shipping cost");

to

// $("#quotes-pane legend a").text("Shipping cost");