MarketPress shopping cart language reverts to default after adding/removing products

This must be an AJAX thing, but I don’t know how to resolve this. When on a French page, then I add a product to the cart (or empty the cart), upon refreshing the cart widget its contents switch back to being in English. It’s the update_cart() AJAX function in marketpress.php that’s generating the HTML fragment for the cart, but looking in there I see all gettext wrappers etc being applied, so don’t know why this is happening? I’ve also tried using calling localization() and textdomain(‘WP’:wink: inside this to force the language translation setup, but no joy… Help!