Usage of weekday in function and xpath

According to the mendix documentation the parseDateTime function points to Javadoc, and says that the option –u returns the weekday number, where Monday = 1, see javadoc The xpath contstraint function as described in ref guide uses the weekday number to retrieve records from the db. Here the documentation says Sunday = 1 I expect both to use the same Weekday as number. Can somebody explain please?
1 answers

In Project Settings -> Model, there is a setting for first day of the week.