iOS 4.3.1 has problems connecting to some Wi-Fi networks

I installed iOS 4.3.1 only on the iPhone 3GS terminal that I have at home and so far I have not noticed any problems with connecting to Wi-Fi networks, but i0n1c claims that for some people such problems exist. He claims that some terminals cannot connect to certain Wi-Fi networks made with certain routers, regardless of whether the terminals are jailbroken or not. Moreover, he claims that the jailbreak solutions released today were initially postponed because it was not known whether the problem with Wi-Fi networks is caused by the jailbreak or an iOS problem. I don't know if his statements are true, but I haven't had any problems so far after jailbreaking with sn0wbreeze on iPhone 3GS, but I may have surprises if I jailbreak on iPhone 4 with redsn0w.

Have you had such problems so far with any terminal?