Excel date issues in Leopard

Hi all,


Currently I am having trouble with dates inside Excel 2004. I am
Mexican and I input dates in the format dd/mm/yy. I have customized
this under International in System Prefs. This used to be a fix so
that any other apps (like Excel) will recognize this as the default
format for date input.

However this is not the case, Excel under Leopard doesn't recognize
16/11/07 as a valid input for November 16 2007. This worked perfectly
under Panther. But does not work anymore.

Any help will be greatly appreciated.