There are a number of third-party "WinZip clones" out there. I can think of "ZipGenius" as one that comes to mind quickly. You can find them on http://www.download.com. These third-party tools might be more forgiving of whatever corruption existsin the file and allow you to recover some or all of the contents.
However, if the file is truly corrupted the odds are that nothing is going to fix it for you. The reason I say this is that there would be no way for a tool which knows nothing about your file to realize that the bytes of the file which might currently be "01 E1 A1" should really be "02 EA 11" instead. You may need to recover this file from a good backup or re-download it, or whatever to get an uncorrupted version.