This thread details how to monitor your event logs to pick out software disk mirror failure notices and email them -- too bad this is not built into Windows.
http://groups.google.com/group/microsoft.public.windows.server.sbs/browse_thread/thread/2edbce4423886573/33ac7644c7afa489?lnk=st&q=windows+software+raid+email+notification&rnum=5&hl=en#33ac7644c7afa489
More current, 2012 for Win7: http://social.technet.microsoft.com/Forums/windows/en-US/5d3c3d5c-38ee-4a3d-9243-17712556eab8/windows-7-has-no-notification-of-raid-failure?forum=w7itprogeneral
tags: mirror, raid, windows