i dont use gmail.
but, i have comcast. my settings in accounts are as follows:
incoming mail server:mail.comcast.net
username: the part before the @ of your email addy
password: your password
outgoing mail server: click server settings button
in the server settings window:
outgoing mail server: smtp.comcast.net
server port: 465
check next to SSL: yes
authentication: password
username: the part before the @ of your email addy
password:your password
these settings have worked for me since comcast took over ATTBI a year or so ago....tho i do frequently get the little lightning bolt. but, i have (maybe erroneously) deduced that this is because i have 2 other computers checking the same account frequently and only one can be logged in at a time. that's my guess anyway.
my 'workaround' for the error message that results in the offline lighting bolt is to hit escape (esc) to the message, then just click the lighting bolt icon...it will then go back online fine without me having to re-enter any password, username, etc.