More than a little disappointing, you cannot set the sender of the outgoing message.
Here is a more general version of the Matthew script that I wrote many years ago and often used. An argument is a string containing exactly what you see in the From: pop-up window.
"Mitchell L Model < dev@software-conce pts.org>"
(It is very difficult to get information about something like this if you are not doing a lot of GUI).
to setFrom(address) tell application "System Events" activate application "Mail" tell pop up button "From:" of window 1 of application process "Mail" click tell menu item address of menu 1 to click end tell end tell end setFrom
The reason I use the parameterized handler is because I use the keystroke macros to bind a key combination for each of my email addresses. Each of them runs AppleScript, which downloads a file containing the aforementioned handler and invokes it with a specific email address. For instance:
property util : load script alias (((path to home folder) as text) & "Scripts:Utilities.scpt") util setFrom("Mitchell L Model < dev@software-concepts.org >")
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