Resent: xs:all fails to validate minOccurs='0'

For schema: xs:complexType name=Invoice_Type xs:all xs:element name=InvoiceNum type=INV_NO_Type minOccurs=0/ xs:element name=InvoiceClass type=INV_CLASS_Type/ xs:element name=Warehouse type=WARE_NO_Type/ /xs:all /xs:complexType Where INV_NO_Type is defined as an Integer,

xs:all fails to validate minOccurs='0'

For schema: xs:complexType name=Invoice_Type xs:all xs:element name=InvoiceNum type=INV_NO_Type minOccurs=0/ xs:element name=InvoiceClass type=INV_CLASS_Type/ xs:element name=Warehouse type=WARE_NO_Type/ /xs:all /xs:complexType Where INV_NO_Type is defined as an Integer,