upgrade evolution and address change

I ran up2date today. One of the items apparently was an upgrade to
evolution from 1.0.3-4 to -6. On top of that, my send server was changed
too. Now I can't get the -6 version to get setup properly. Right now I'm
running from the -4 on my laptop which hasn't been updated, yet.

Q1) Changing the server id: originally I get email on earthlink and
that's still ok. But sending used to be via user@qwest.net, and is now
newuser@qwest.net. When I changed the userid in the send part, it would
not prompt for a pwd. POP b4 SMPT is what's set. Now I get a SMPT server
does not support auth type PLAIN.

Q2) Barring that fix, if I need to go back to -4, how do I do that
safely?

pete