Forwarding this from a Fedora bug:
http://bugzilla.redhat.com/show_bug.cgi?id=162434

I confirmed this is still present in Evolution 2.12.


Description of problem:
When composing a new email message with Evolution, case is not preserved when
typing in an email address.  You could type 'tim@cyberelk.net' and end up with
'Tim@cyberelk.net'.

Version-Release number of selected component (if applicable):
evolution-2.2.3-1.fc4

How reproducible:
100%

Steps to Reproduce:
1. Create a contact for 'Tim Waugh' with email address twaugh@redhat.com
2. Compose a new email, typing in the address 'tim@cyberelk.net'.
  
Actual results:
To: field contains: Tim@cyberelk.net

Expected results:
To: field contains what you actually typed in.

Additional info:
Worked fine in FC3.