Is updating and web surfing on wifi safe with dsi?

Is this safe, I heard that nintendo can detect machines with modified cards in them and stop them working, any truth to this?
cheers
Justin

No. The only way they stop your carts from working is if you update to 1.4 firmware, and that has a workaround.

thanks mike, so it wont auto upgrade or anything like that? with the 1.4 firmware do you mean the one for the flashcart?