They have a version of t-bird in the distro
it's called icedove. It seems they have issues with the trademarking of the terms firefox and thunderbird, and so have renamed it so as to avoid the unfreeness of those terms.
Before I fire it up, I'm going to look at copying my thunderbird profile to my home directory, so I can just start up where I left off.
I'm currently making enlightenment. I've got all the libraries etc made and installed, and am making the main app now. After that, it's make install and hopefully I'll be able to check it out....