Fixed
The bug has been fixed. See the Version Fixed and Additional Information, if applicable, for more information.
Workaround
Refer to the following documentation for the list of available vertical coordinate systems,esrSRVerticalCSType Constanr<a href="http://edndoc.esri.com/arcobjects/9.2/ComponentHelp/esriGeometry/esriSRVerticalCSType.htm" target="_blank">http://edndoc.esri.com/arcobjects/9.2/ComponentHelp/esriGeometry/esriSRVerticalCSType.htm</a>