Typo about documentation page

There is a bug (are is 2 time but they are are type-safe ) in this page
http://doc.qt.nokia.com/4.7-snapshot/propertybinding.html

See
Types of PropertiesProperties may bind to different types, but they are are type-safe. That is, properties only allow you to assign a value that matches the property type. For example, if a property is a real, and if you try to assign a string to it you will get an error.