Yes indeed it does mean that distributing custom files or the client is in direct violation of this act. The fact that there may or may not be custom graphics and maps within the files is neither here nor there because Electronic Arts/Mythic Entertainment owns the property rights of the file types extensions used (example: .mul / .uop). Also keep in mind that even though you put your own graphics into the game doesn't mean you escape copyright infringement; remember, we all use the same graphics and animation that were already installed into the game by Electronic Arts/Mythic Entertainment as well.
Up until now, Origin Systems Inc./Electronic Arts/Mythic Entertainment, has never officially condoned owning, operating, or even playing on any emulation server as per paragraph 5, section D of their Terms of Service. However the company has unofficially allowed RunUO and other server emulators go about business as usual for reasons only Ryan really knows and the rest of us can only speculate. My theory is that they like having us around to pull ideas from and market them if they see something they think will make money; kind of like an unspoken alliance where they say, "hey you can have your servers, but you may not charge for them or use our work as your own"; hence why hex editing the client has been a big no no and no one offers to help do it, even though most of us here have done it at one time or another.
The work around is simple: the above notification was taken by me and sent to Otim Pyre... simply do a property check on the UO.exe (I would do a check on all of the .exe files just to be sure)... and look for the Digital Signatures tab. If your UO.exe doesn't have one then you can use and edit that client version and its associated data without any troubles. If your .exe files do have the Digital Signature tab, then Origin Systems Inc./Electronic Arts/Mythic Entertainment reserves the right to eventually go after and legally shut down any emulated server they deem a threat to their pocket book. Don't kid yourselves, everyone here has their own explanation of why this wont happen.
History proves that it isn't necessarily that it wont happen, it could happen, and it did happen with Sony Entertainment Online and Blizzard Entertainment. We've just been lucky so far that Origin Systems Inc./Electronic Arts/Mythic Entertainment has been nice enough to allow us to continue to do what we do, but I see us pushing the envelope by using the newer clients and continually finding ways around the system which could put some of you in jail or face hefty fines. So do what you all are going to do, but keep this warning in the back of your mind because this Federal Act is very real and our government is getting more power hungry. The earliest client I know of that doesn't have this Digital Signature tab is client version 7.0.23.1... best of luck to everyone
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Digital Millennium Copyright Act: Info:
http://en.wikipedia.org/wiki/Digital_Millennium_Copyright_Act
criminalizes production and dissemination of technology, devices, or services intended to circumvent measures (commonly known as digital rights management or DRM) that control access to copyrighted works. It also criminalizes the act of circumventing an access control, whether or not there is actual infringement of copyright itself. In addition, the DMCA heightens the penalties for copyright infringement on the Internet.[ Passed on October 12, 1998, by a unanimous vote in the United States Senate and signed into law by President Bill Clinton on October 28, 1998, the DMCA amended Title 17 of the United States Code to extend the reach of copyright, while limiting the liability of the providers of on-line services for copyright infringement by their users.