The link to the "Copying Parallel Line Features" topic in ArcGIS Desktop 9.3 Web help is broken:
http://webhelp.esri.com/arcgisdesktop/9.3/index.cfm?TopicName=Copying_parallel_line_features.
Use the 9.2 version as a reference:<a href="http://webhelp.esri.com/arcgisdesktop/9.2/index.cfm?TopicName=Copying_parallel_line_features" target="_blank">http://webhelp.esri.com/arcgisdesktop/9.2/index.cfm?TopicName=Copying_parallel_line_features</a>