Can anyone see why the following to cursors would NOT be union compatible?

Select invoice.pk_id, ;
	invoice.dinvDate As invDate, ;
	invoice.cCompanyName, ;
	invoice.cInvNum, ;
	invoice.cprojectnum, ;
	invoice.cprojectName, ;
	invoice.cJobNum, ;
	invoice.cJobName, ;
	{} As pmtDate, ;
	00000000.0000 As pmtAmount, ;
	Space(50) As cRef, ;
	"I" As rowType ;
	from invoice ;
	where invoice.pk_id In ;
	(Select pk_id From rsOutInv) ;
	order By invoice.cInvNum ;
	into Cursor rsJustInvs

Select Payment.fk_invoice_id, ;
	{} As invDate, ;
	Space(0) As cCompanyName, ;
	Space(0) As cInvNum, ;
	Space(0) As cprojectnum, ;
	Space(0) As cprojectName, ;
	Space(0) As cJobNum, ;
	Space(0) As cJobName, ;
	payment.dDate As pmtDate, ;
	payment.yAmount + yTax As pmtAmount, ;
	payment.cRef, ;
	"P" As rowType ;
	from Payment ;
	where Payment.fk_invoice_id In ;
	(Select pk_id From rsOutInv) ;
	order By Payment.fk_invoice_id ;
	into Cursor rsJustPayments

And the union:

Select * From rsJustInvs ;
	union ;
	select * From rsJustPayments ;
	into Cursor rsPrint