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Possibly - Read our guidelines and send us a little more information so we can consider the possiblities! If you'd like to contribute another person's work (perhaps something you believe is in the public domain) you'll want to confirm that you have the right to do so; read Project Gutenberg's Copyright How-To for more information.
This seems to be related to Windows built-in zip utility. Some readers have reported better results with 7-zip.
If you're using Windows, removing ".php" from the filename and adding ".pdb" to the file should fix the problem. Microsoft Knowledge Base Article - 307859 "How to change file associations in Windows XP" may be useful if you're having trouble changing the file extension.