fail to connect to public wifi networks with cyanogenmod

I changed my pre-installed OS to Cyanogenmod 9 on my Xperia Neo V and since then I cannot connect to any free public network that requires simple registration (like airports, cafes, etc). My phone does connect to the networks (it says connected) but when I open the browser (Opera) to register it never connects, getting a failed to connect message after a while. Does this has to do with this other problem I also have? To solve that problem I had to delete the dhcp folder. Maybe I deleted some other important files there?