The iSmartDS team have released an update for their iSmart Premium card to allow 3ds compatibility.
1. Download firmwareV4_3DSfix.zip
2. unzip the file
3. You should see file ISMART_firmware 4.nds
4. Copy ISMART_firmware 4.nds to your TF
5. Run ISMART_firmware 4.nds as you would a normal game