First I pressed ctrl + ; , I got the current date in this format say 15-9-2010 in MS Excel, then I pressed ctr?

First I pressed ctrl + ; , I got the current date in this format say 15-9-2010 in MS Excel, then I pressed ctrl+shift+# or 3 and I got the date in the format say d-mmm-yy i.e. 15-Sep-10. Now I want this date in this format say d-mmm-yyyy i.e.15-9-2010 after pressing ctrl+shift+# or 3. The computer and software always show the date in this format d-mmm-yy i.e.2-Sep-10. I am using Office 2000 and Windows XP. In regional settings, I have chosen ‘English (United States)’ as regional options and in short date format I have chosen d-M-yyyy and long date format is d-MMM-yyyy.