I was delighted to see Google's announcment of IMAP access to gmail, then disappointed to find that my gmail settings page didn't provide the IMAP option.
Google evidently don't know how to say "IMAP" in english english!
Solution: Log in to Gmail. Go to your settings page. Change your language setting to English (US); Save Changes and the option appears: Forwarding and POP/IMAP. Use this tab to enable IMAP access, then you can go back to English (UK).