jquery update 1.0 incompatibility with UC1.5

I'm running jquery update version 5.x-1.0 on the site (ie jquery 1.1.2).
When I go to /cart/checkout the page gets a JS error, and the "shipping quote" part of the checkout screen doesn't work.
In addition, there is a further message in the "payment options" pane, which says "Javascript must be enabled to view the total order preview". (but JS is enabled)

If I install jquery_update 5.x-2.0 (jquery 1.2.6) then the checkout seems to behave correctly, including shipping quotes, payment methods, and there are no js errors on the page.

It looks to me as though there might be a compatibility issue between jquery 1.1.2 and UC 1.5. I also tested with 1.6 and get the same result.

NB I've also posted a similar description back at the UC forums here. (wasn't sure where the best place was to report this)