QueryBuilder is not DBindependent for column check unequal 1

Classic Servoy
1

For FoxPro DBF I used:

.add( simbaBookingQuery.columns.storno.not.eq( 1 ) )

but for MS SQL I have to change the above to:

.add( simbaBookingQuery.or
   .add( simbaBookingQuery.columns.storno.eq( 0 ) )
   .add( simbaBookingQuery.columns.storno.eq( null ) )
)

Why does not.eq( 1 ) not work for MS SQL?