Created attachment 37103 [details] lookup_missing_param.patch In `=VLOOKUP(A1,A2:C3,2,)` the last arg was seen as TRUE in POI, but FALSE in Excel 2003 and Excel 2013. This patch makes POI behave like Excel in this regard. I have added some tests to verify the bahvior.
Created attachment 37104 [details] LookupFunctionsTestCaseData.xls To be placed in test-data\spreadsheet\LookupFunctionsTestCaseData.xls
Applied via r1882827, thanks for the patch and the updated test-case!