Diference between air runtime in and out flex builder

[Diogo]

I was using flex bluider 3 with flex sdk 3.0 and i needed to change for the flex sdk 3.4 because the flex sdk 3.0 don't have the attribute timeout in the class XMLSocket. The problem is when i use the flex sdk 3.4, set the timeout like "xmlsocket.timeout = 10000;" and run application under flex builder 3 i get the error "ReferenceError: Error #1056: Cannot create property timeout on flash.net.XMLSocket.". When i run the .air generated out of the flex builder, the error don't occurs and the application work normal.
The flex builder have a own air runtime? it's don't use the installed air runtime of the my machine?

Thanks,
Diogo