Dotted lines in Crow's Foot notation in Visio 2003 - HELP!

Database modeling with crow’s foot notation.The crow's foot notation is
almost the only one meeting academic standards such as explained in the book
'Database Systems' , 4th Ed., T. Connolly, Addison-Wesley,2005. However I
could not find the use of a dotted line to explain 'identifying' and
'non-identifying' relationships. Now I have spent a lot of time creating the
diagram, but I need to get rid of the dotted lines unless I can show that
anyone else other than Microsoft is using this concept. If you happen to know
why this decision was made and whether there are academic publications or
whitepapers related to the decision of using dotted lines to show the
difference of Identifying Relationships, please email me immediately to
).