I guess you missed this paragraph:

"This article describes the initial step of porting Eiffel to Microsoft .NET, resulting in a now obsolete "Eiffel#" intermediate version that supported a subset of the Eiffel language. Starting with version 5.1 (November 2001), Eiffel for .NET supports full Eiffel, and is identical to the language supported on other platforms with multiple inheritance and all other advanced Eiffel mechanisms such as agents."