Vertical factor parameters in Path Distance Tool

[BenjaminZank1]

Hello,
I was wondering if anyone out there know's when (at what version of release) the Vertical and Horizontal factor parameters were added to the Path Distance tool in Spatial Analyst.

Thanks,
Benjamin Zank

[DanPatterson_Retired]

help files 
9.1  http://webhelp.esri.com/arcgisdesktop/9.1/index.cfm?TopicName=welcome
9.2  http://webhelp.esri.com/arcgisdesktop/9.2/index.cfm?TopicName=welcome
9.3  http://webhelp.esri.com/arcgisdesktop/9.3/index.cfm?TopicName=welcome
10   http://help.arcgis.com/en/arcgisdesktop/10.0/help/index.html?TopicName=welcome

search using pathdistance would show the differences, I don't have the 9.0 help file links anymore