from the s60 gmail setup page, the first step is configure for IMAP. is this not true IMAP?
http://mail.google.com/support/bin/answer.py?answer=78887&topic=12920
Here are the steps:
Symbian S60
To configure IMAP for your Symbian S60 device, just follow these steps:
Enable IMAP in your Gmail settings.
Select 'Messaging' > 'Options' > 'Settings' > 'E-mail' > 'Mailboxes.'
If you have never set up email on your phone before, select 'Yes' to define a new mailbox. If you already have other mailboxes, select 'Options' and then 'New mailbox.'
Select 'Start' to begin the setup wizard.
Select 'IMAP4' and then 'Next.'
Enter your Gmail username (including '@gmail.com') as the email address and select 'Next.'
Enter 'imap.gmail.com' as the incoming mail server and select 'Next.'
Enter 'smtp.gmail.com' as the outgoing mail server and select 'Next.'
Select the appropriate access point and then 'Next.'
Enter a descriptive name for the email account mailbox name.
Once your mailbox is set up, select it from the email mailbox settings screen.
Select 'Connection settings' > 'Incoming e-mail.'
Enter your Gmail username (including '@gmail.com') and password.
Select 'SSL/TLS' for your security (ports) and define your port as '993.'
Select 'Back.'
Select 'Outgoing e-mail.'
Enter your Gmail username (including '@gmail.com') and password.
Select 'StartTLS' for your security (ports) and define your port as '587.'
Select 'Back' and change any other settings according to your preferences.