hello folk's

i have a m3i zero card and when i want to play pokemon white and i want to do wifi.
it is saying there is no acces point, but if i go on internet on nintendo dsi it works.
so i have wifi connection but when i do it on pokemon it doesnt work.
is there any way to fix it.

is it true if i buy a dsi xl and put my m3i card in. does it work then with wifi?

and one last question
does the dsi xl support m3i zero card of systeem version 1.4.1 or 1.4.2
i have now on my DSI (not xl) 1.4U