My phone has been locked (too many pattern attempts). To unlock I need to enter username and password on my gmail account. This is the only way I can unlock it. I cant launch any activities, even to turn on wifi connection. Without internet connection I can't sign in to restore my phone.
Maybe there is any command in adb to turn on my wifi connection, so I can use my phone?
Unfortunately the only way I could resolve my problem is to root the device.
Here is a good tutorial for Nexus S:
http://nexusshacks.com/nexus-s-root/how-to-root-nexus-s-or-nexus-s-4g-on-ics-or-gingerbread/