I found this on the SuperCard forums,
"1. Patch the US Version using XPA Patch
2. Unpack the patched version using DSLazy
3. Unpack the EU Version using DSLazy
4. Goto EU_Unpacked/data/German (or whichever language you prefer) and copy the contents over the US_Unpacked/data/English directory
5. Re-build a *.nds file using DSLazy
6. Copy the newly created file to your flashcard
7. Works great, it's cracked and german/french/spanish/italian as well now..."
Tell me if it doesn't work.