Stop Word from automatically updating date field when document is opened

Hi,

I recently installed Office 2003 and since then whenever
I open a word document with a date field in it the date
is automatically updated to the current date. In Word
2002 if I didn't want the date updated I'd be able to hit
the undo button and the date would revert back to what it
was before. However, in Word 2003 I am not able to do
this as the undo button is not active.

This is a major problem for me since if I typed a memo
two weeks ago and want to print out another copy later,
it will show the current date and not the date when I
created it. Imagine typing something a year ago and when
your boss asks you for a copy a year later it looks like
you just typed it.

Is there any way to prevent Word from automatically
updating the date field, or any other field, without you
expressly wanting to? I'd hate to have to revert back to
Office XP just to get away from this one problem.

Thanx.