Are you doing it like this:
=TEXT(12/31/1900,"mmm")
=TEXT(11/16/06,"mmm")
=TEXT(9/17/07,"mmm")
If so, what you're getting is:
12 divided by 31 divided by 1900 = 0.000203735144312394
11 divided by 16 divided by 6 = 0.114583333333333
9 divided by 17 divided by 7 = 0.0756302521008403
In the formula evaluation the decimal portion is truncated and you're left
with 0.
So the formula is evaluating as serial date 0 or 1/0/1900 = Jan.
That's one of Excel's anomalies, you can calculate a date to be the 0th day
of a month. This can be taken advantage of in that the 0th day of the month
actually refers to the last day of the previous month. Starting to get off
topic and it can be complicated trying to figure out in what situations this
isn't always the case. For example, if the 0th day of the month refers to
the last day of the previous month then why doesn't 1/0/1900 return Dec? Yet
WEEKDAY(0,2) retruns 6 (Saturday) which is referring to Saturday, Dec 31
1899. Did I open a gigantic can of worms? <BG>
So, try your formula like this:
=TEXT("12/31/1900","mmm")
Biff