[Dovecot] imap proxy for Gmail

Hello, b

I have a situation were I want to be able to give teachers access to their Google apps for education email through Squirrelmail. The network that they are on blocks gmail.    I am able to get Squirrelmail to communicate with Gmail via imap.  I am looking at getting persistant imap connections to improve the user experience.  I have looked at IMAPPROXY  but this application is not compatible with the gmail imaps (ssl-encrypted imap over port 993).   I recall reading somewhere that Dovecot has a built in imapproxy that could be used for this. 

Can someone please point me to documentation or other information on how I might achieve the above stated goal?

Thanks,  Kafriki