Pastel Pervasive SQL problem

[LoanB]

Hi I have the following SQl statement which Im executing in pervasive v9.

The stateemnt works except fot the last conditionion namely the:

AND HistoryHeader.ClosingDate <= '8/30/2007'

Complete Statement is:

SELECT CustomerMaster.UserDefined05 AS 'TRIP'
, CustomerMaster.UserDefined04 AS 'TOWN'
, CustomerMaster.CustomerDesc AS 'CUSTOMER'
, HistoryHeader.DocumentDate AS 'ORDER DATE'
, HistoryHeader.ClosingDate AS 'PLAN DATE'
, HistoryHeader.Message01 AS 'TIME'
, HistoryHeader.Message02 AS 'USER'
, HistoryHeader.SalesManCode AS 'ORIGIN'
, HistoryHeader.Message03 AS 'KEEP'
, InventoryCategory.ICDesc AS 'PRODCATDESC'
, Inventory.Description AS 'PRODUCT NAME'
, Inventory.ItemCode AS 'PRODUCT CODE'
, Inventory.UserDefText01 AS 'PRODUCT SIZE'
, Inventory.UserDefText02 AS 'PRODUCT FLAVOUR'
, HistoryLines.Qty AS 'PRODUCT QTY'
, HistoryLines.UnitPrice AS 'UNIT PRICE'
, HistoryLines.DocumentNumber AS 'INVOICED'

FROM CustomerMaster
INNER JOIN HistoryHeader
ON CustomerMaster.CustomerCode = HistoryHeader.CustomerCode
INNER JOIN HistoryLines
ON HistoryHeader.CustomerCode = HistoryLines.CustomerCode
INNER JOIN Inventory
ON HistoryLines.ItemCode = Inventory.ItemCode
INNER JOIN InventoryCategory
ON Inventory.Category = InventoryCategory.ICCode

WHERE CustomerMaster.UserDefined05
IN ('PE')

AND HistoryHeader.ClosingDate <= '8/30/2007'

The Error is:

[LNA][Pervasive][ODBC Engine Interface]Error in predicate: HistoryHeader . ClosingDate <= '8/30/2007'

Any ideas please?