Like I said in my other post on one of your other threads, I can help but think you just need to update to a newer ROM so try this one
here.
Just so you and everyone else know it is a WM5 ROM nd is named Kirvins 3.5 build 1.02. It is very fasy and stable and I think you will like it. Mind you it is for VZW users so dont no sprint userd go trying to use it and PM me on why it doesnt work for them. With it you will have no wifi issues. IE is up to date and like I said, I think you will like it and find it much more easy and stress-free.
For WiFi on it you simply go to your Connection Mngr and enable WiFi. From there go to Menu -> WiFi Settings -> choose the WiFi connection and this is where you will start to configure the wireless settings. So on this first screen just go next and the next screen will already have what type Authentication and Data Encryption Type you are going to use on this particular connection so just enter your encryption key.
Now remember that WM5 will do both WEP and WPA and if you are using WPA then make sure you choose TKIP.
So after entering your key click next and then finish. It will go back to the screen with the available WiFi spots and should show you connected although it could still take a few seconds. Once it is connected you can just go and open IE and surf. I am not going to get into specifying IPs and DNSs or what adapters to choose to specify that because if you use the ROM I linked above then you will be hard resetting and everything at default will be fine.