GMail set up is interrupted

I'm unable to set up a conection with my GMail account. This is the way I try to do

1. Open Settings and select E-Mail, contacts, calendar.
2. In the section Accounts, press Add account.
3. Press the Google label and let the login procedure start.
4. Enter your user name and password.
5. The service responds by presenting you with a list of what iOS will do, like: handle your mail, handle your calendars, etc.
6. Press the button Accept.
7. The iPad starts to display a panel with settings, indicating which features will be synchronized. The panel barely shows before it disappeares again, returning to the state where you see which accounts can be set up. The Google account hasn't been set up thought.