I don't know. I am on my iPhone and on 3G and I am not having any problems.
Maybe it is your carrier.
Are you on O2?
O2 restricts user access to sites that may be of an adult nature on their network - you need to prove that you're over 18. You can do this at any O2 shop but you have to be prepared to do it again once every year or so. There's probably a way of doing it online.
Warning: The opinions above are those of an anonymous individual on the internet. They are opinions, unless they're facts. They may be ill-informed, out of touch with reality or just plain stupid. They may contain traces of irony. If reading these opinions causes you to be become outraged or you start displaying the symptoms of outrage, stop reading them immediately. If symptoms persist, consult a psychiatrist.
Why not read some stories instead
NEW! Want a quick read for your coffee break? Why not try this... Flash Erotica: Scrubber The same thing happened to me, but I'm on three. Funnily enough it happened on the same day. Weird, but I remedied it, I think, by using the stock browser and then switching back to chrome. I've no idea why that helped, or if it was just a coincidence, but I didn't question it.