When the too many pattern attempt unlock screen appears, in my phone I tried restart, remove the battery for while and then restarted nothing worked. It requires your Google username & password which you gave when u Synced the phone with Google account.It will not detect it as the correct combination if not connected to the internet. So if you can do that you can save all your files and contacts.
Method I Used:
1. Press Power on Button
2. Select activate Data Network Mode. Then you can generate application specific password.
3. Use that to unlock the phone.
Thats it. Hope its useful.