Cart pane always displays default store currency prefix, regardless of currency setting for products

Please note, I've been able to reproduce this issue with 3 different multi-currency modules (uc_multiprice, uc_cck_currency and longwave's multicurrency sandbox mode), so I am suspecting an issue either in uc_cart or, perhaps, in the uc_price() function in uc_store.

Steps to reproduce:

1. Install and configure any of the above modules.
2. Define a Product, and depending on the method required by the respective multi-currency module, add a price that is not in your default store currency.
3. Add the product to the cart using a non-default currency (as determined by the multi-currency module... for multicurrency, you can simply add ?currency= to the cart link, for multiprice you set a specific billing country, for uc_cck_currency you modify the user's preferred currency).
4. Observe that while both the cart and the checkout cart pane correctly set the price in the non-default currency, the prefix remains locked to the store's default currency.
5. Observe further that while the Cart contents pane gets the prefix wrong, the "Order total preview" box in the Payment method pane has it right. The order is thus checked out with the correct price, but prior to that the experience is quite confusing for the user.

Digging into this I'm suspecting (but please don't take this as certainty) an issue in the way uc_checkout_pane_cart() invokes uc_price(), but that's really just a hunch.

I would hugely appreciate all input in getting this sorted. Happy to act as a guinea pig if needed.