IPV6, Fedora and apps

[Douglas Phillipson <phillipd oem doe gov>]

Do network applications written for Fedora, or any Linux distro for that 
matter, require any modification to work with IPv6?  or is that a 
"TRANSPARENT" change in the protocol stack under the application layer? 
 Is there a different API for IPv6 for network apps, socket servers, etc?

Thanks

Doug P