Runs on any language DSi!
Now that the beta testing is completed; the Acekard Team have released their update tool that fixes the known compatibility issue of the Acekard 2i running on DSi's that have their system language set to anything but English.
Unlike the usual loader updates, this fix updates the actual cart firmware, so be careful when running (and ensure you have a charged up battery). The fix is simple to run though -- just copy the .nds file in the attached zip file to the root of your micro SD card, and then proceed to boot up your DS. The automatic update will then run.