RC4 compatibility testing

[Jim choate]

> 
> > And then latter if it was patented I would be exempt from paying
> > royalties on my product, no?
> 
> Ahem.
> 
> If an invention is successfully patented, any use you make of it
> requires royalties even if that use began before the patent was
> granted.
> 
> However, RC4 is probably not patentable at this point -- unless Bidzos
> has a "submarine patent" in process, which I wouldn't put past him.
> 
If there was considerable use prior to the patent application then there 
would be a good case to be made that it was in the public domain because
of this use.