Requirement: selector.property.conversion

The conversions that apply to the get methods for properties do not apply when a property is used in a message selector expression. For example, suppose you set a property as a string value, as in the following:
myMessage.setStringProperty("NumberOfOrders", "2");
The following expression in a message selector would evaluate to false, because a string cannot be used in an arithmetic expression: "NumberOfOrders > 1"

See:

• Section 3.8.1.1, Message Selector Syntax