It seems that in Windows 7, Jaws is defaulting to using the scripts for Windows Mail when running Outlook Express.  I did not notice this before myself, but it would explain why the Outlook Express scripts are not being initiated.  After examining the scripts for Outlook Express, I discovered the reason why this occurs.  Apparently, there is a bit of code in the "Auto Start Event" function which checks to see if you are running Vista.  If the function returns "true", then it switches to using the Windows Mail scripts instead.  The Jaws scripting language returns "true" when performing the check even if you are running 7 and probably 8 as well.  I suspect this was done because Outlook Express was replaced in Vista by Windows Mail, but the two programs still have some script components in common.  In any case, the solution is to either delete or comment out the lines which perform this check in 
Outlook Express.jss.

For the sake of convenience, I have included the modified scripts in this archive.  Just copy them into the folder, 

C:\Users\UserName\AppData\Roaming\Freedom Scientific\JAWS\VersionNumber\Settings\enu

Replacing "User Name" and "Version Number" in the path as appropriate with your user name and the version of Jaws you are running.  For example, 

C:\Users\Carlos\AppData\Roaming\Freedom Scientific\JAWS\14.0\Settings\enu

Regards,
Carlos