Wifi shield infrastructure vs ad-hoc

Hi!

Is there a way to use the Wifi shield in ad-hoc mode or does it only support infrastructure mode? I did not find the answer on the Wifi shield page and I tried googling it but I didn't find any convincing answer (even if some people seem to believe it is only infrastructure mode). I am new with wireless communication so maybe it is obvious but not for me :~

Thank you for any answer.

Edit : I am talking about the Arduino official Wifi shield