Inheritance

Hi,
 
Assume we have:
 
myclass:PassengerVehicle  rdf:Type  rdfs:Class
myclass:FourPassengerVehicle  rdfs:subClassOf  myclass:PassengerVehicle  
myclass:FourPassengerVehicle  myprops:seats  "4" 
myclass:Volkswagen  rdfs:subClassOf  myclass:FourPassengerVehicle  
myobjects:myCar  rdf:Type  myclass:Volkswagen  
 
then:

*	does "normal" RDF/RDFS-compliant software "know" that all instances
of myclass:Volkswagen have 4 seats?
*	and does it know that myCar has four seats?

or in other words: does specialization (rdfs:subClassOf) and typing
(rdf:Type) actually and reliably lead to inheritance of properties?
 
Regards,
Hans
 
PS I have been unable to locate such "normal" software (IDE, validators,
browsers, etc.) that can be used without being a programmer (I'm a data
modeller) Any hints?
____________________________
Hans Teijgeler
co-author of ISO 15926-2 <http://www.infowebml.ws/ECM4.5/ECM4.5.html> 
author of ISO 15926-7
website www.InfowebML.ws <http://www.infowebml.ws/> 
e-mail hans.teijgeler@quicknet.nl
phone +31-72-509 2005