Best Mode v. Copyright

I'm curious if anyone on either the patent or copyright list has considered the following dilema?

For a variety of reasons, in particular best mode requirements, many practitioners routinely submit code listings with their patent applications involving computer-related inventions.

Query: Whether registered or not, the code is copyrighted. Therefore, upon expiration of any patent(s) which may issue, since the copyright term is semi-infinitely longer, how can the software listing satisfy the best mode requirement since the copyright prevents one skilled in the art from practicing the invention??

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Bruce M. Bertram       <URL:mailto:bmb[_at_]bmb.com>     finger for public key
Patent Attorney        <URL:http://www.bmb.com/~bmb/>
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