If Jet Essentials is returning dates (i.e. Posting Dates or Period Start dates) four years ahead of the year that you are filtering for, you may have your workbook set to use the 1904 date system. In Office 2000 and XP, you can change the date setting in the Tools/Options/Calculation menu. Turn off the check box next to the "1904 date system" setting.
If you have your Windows Regional Settings configured to treat dates as MM/DD/YYYY and you are using dates in Jet Essentials as DD/MM/YYYY, you will either get unexpected results or #VALUE, depending on which dates you are specifying. You can create the same sort of problem with some database servers that have a built in date formula specification. For some database servers, the date format can be configured independently from Windows, so you need to know what date format the server is set to.