How to fix iPhone 3G with wifi not working and no service?

Hi can somebody help me? I forgot my passcode in my iphone 3g 8gb, so i found out that there's no way but to restore it. I used an iphone firmware 4.0.1 and jailbreak it by red snow. I was happy to see it activated but there's no service with simcard inserted and i cannot connect to our wifi. It's not like the others with greyed out wifi, just showing: Wifi____Not Connected> and No Service

I already tried to go on:

1. Settings>General>Reset>Reset Network Settings

2. Airplane Mode On>Wifi Off>Cydia Settings Ok>Airplane Mode Off>Wifi On> Others_Cancel_Others_Cancel

3. Settings > General > Reset > Erase All Content and Settings

4. Settings> General> Network> Enable 3G Off> Restarting iphone by holding on power and home button until it turns off and continued to hold it until the apple logo shows

I'm here in philippines and changing sim card to at&t etc will surely be not working for my case, and I think there's a real problem with my iphone, but if it needs techinical skills like opening it with suction cup I may leave it to the expertise of a repair man.

History: I dropped this iphone in the swimming pool before. For my bluetooth and imei it's ok.

Thanks in advance! God bless!