JSI Tip 10298. User name mapping performs one-to-many mappings in a single direction only?

Microsoft Knowledge Base Article 269736 contains the following summary:

This article discusses the User Name Mapping component of Microsoft Windows Services for UNIX. The User Name Mapping component can perform one-to-many mapping, but User Name Mapping can perform this task only one way, from a Windows-based computer to a UNIX-based computer.