date command question

From: <gwertz_at_BISYS-Plans.com>
Date: Mon, 03 Apr 2000 08:29:19 -0400

Is there a way to get the date command to return yesterdays date? I can do
it by putting the day and month into seperate variables and subtracting 1,
but then it gets ugly if today is the 1st.
Received on Mon Apr 03 2000 - 12:30:09 NZST