Setting Up Secure IMAP On the P910
Finally I managed to setup IMAP mail on my Sony Ericsson P910. Apart from keying in all the parameters, it was necessary to get some insider information about the P910 and secure imap. The P910 can and will use STARTTLS on SMTP connections (nice), even asked for my self-signed server certificate. But it uses STARTTLS also on the imap connection exclusively. The IMAPS port 993 is not used, leave port on 143 and check the "secure" box. My standard so far was to allow only imaps on my server. Will have to think about changing that.
Also a bit stupid: It closes the GPRS connection after each action. Maybe there is a setting to change that. GPRS connections don't cost if left open.