I asked James Vasile, of the Software Freedom Law Center, to comment on this. (For those who don't recall, the SFLC officially represents the Wine project on legal matters).
This is essentially what he had to say (and James, correct me if I get anything wrong :-/):
If you are employed to do programming (even at a university), or have made an agreement with your employer, school or anyone else saying it owns software you write, then you and we need a signed document from them disclaiming any rights they may have to the software. The disclaimer should be signed by a vice president, general manager, or anyone else who is authorized to assign software owned by them. Here is a sample wording:
As a general rule, get everything in writing. The below will suffice. Email is fine, paper is better. The project needs a copy (or, better yet, the original) of the document.
Here's some sample text:
ACME Corporation ("Company") hereby disclaims all copyright interest in the code written by Jane Doe for the program "[insert name of program]" ("Program"), including original Program code and documentation and support files, changes and enhancements to the Program and files, and any future modifications of the Program and files. We do not consider the code as work made for hire for us. Company affirms that it has no other intellectual property interest that would undermine this release, or the use of the Program, and will do nothing to undermine it in the future.
[signature of John Smith], 30 March 2006 John Smith, Vice President, ACME Corp.
Ideally, you would obtain this in writing and then get this on to James (vasille - at - softwarefreedom - dot - org, or use snail mail/fax from their web site).
Cheers,
Jeremy