This tool can help with importing and exporting policies and vocabularies in BizTalk Server 2004. This tool supports the use of a configuration file to limit what is imported and exported. This should also work for BizTalk 2006.
Get more information from the original blog post on this topic: http://www.biztalkgurus.com/blogs/biztalk/archive/2006/03/21/BizTalk-Server-2004-Rules-Engine-Deployment-Tool.aspx