[ubuntu] Evolution App - will not accept port 993

Under Ubuntu 14.04 this email app (ver 3.10.4) will not configure its IMAP settings correctly.

When setting up IMAP - via Edit/Preferences/Mail Accounts/"accountname settings"/Receiving Mail/Configuration/... When setting the server port value. My ISP requirements are for port 993. This is selectable. BUT it will not save that value.

Attempts to check/refresh the server generate error message: "TCP connection reset by peer". Connection fails - no mail headers are transferred.

Upon returning to this dialogue box the (default) port value remains at 143. Multiple attempts made - not successful at getting the 993 value to stick.

Attempted to include ":993" at the end of the "servername" but this compounds the error by referencing the server as "servername:993:993".

Until I can resolve this concern my transition to Evolution is stuck.
[ Does that make me a Darwinist "transition to Evolution". Get it??? ]

Thanks in advance for your help and assistance.
Cheers
Kevin