Install

Those notes are for OpenSolaris only.
To install Thunderbird on OpenSolaris,

Download package from mozilla

e.g: bzip2 -d thunderbird.bz2

pfexec pkgadd -d ...

do a link:

pfexec ln -s /opt/sfw/lib/thunderbird/thunderbird /usr/bin/thunderbird

Profile

To share one's profile between a Windows and a Linux machine (actually, whatever OS !), a solution is to put the profile in a shared directory. To do so, launch thunderbird with the profilemanager option

thunderbird -profilemanager

and then, create a new profile & configure its directory.

Gmail settings

pop.gmail.com, SSL always
imap.gmail.com, settings for Thunderbird
smtp.gmail.com, TLS always, port 587, with authentication

Lightning

Lightning for Solaris is available from mozilla.