Grayed out screen + "Connecting" message.

It's not what happens when you connect to a wifi network. It's more specific than that. It's the screen that appears while the iPhone is attempting to auto-connect to a wifi network, for example, an AT&T wifi hotspot at Barnes & Noble.

I've personally been to a BN recently specifically to try out this new feature and I have to say... it takes FOR-EV-ER to connect.

I have no guesses about what made yours try to do that, maybe someone started up a wifi network named attwifi or something for 2 seconds near you? I dunno. I just wanted to point out more specifically what was happening there.

 

I've noticed this with WiFi on, when it tries to login to a WiFi-network that requires a login (not a password for the actuall wifi-connection, but to access internet through it). It sometimes "hangs" and Safari is greyed out and there's the Connecting-message. I usually just close safari and go to turn off wifi and then go back on 3G.

 

That happened to my 3GS a few times a week when I was switching wifi on and off in settings. It was off when in didn't need wifi connection and when I did, I switched it on and went on browsing with Safari. I didn't matter if the network was password protected or not. Then I turned wifi on in settings, so now it's always on and that gray screen didn't occur anymore. But when I was in Bolgaria on vacation I tried to connect to some unprotected wifi spot and it did that gray screen everytime, even when I forced quit Safari and did a flight mode on/off solution which worked everytime with this problem. I guess some network and iphone connections have certain problems.