SetPlaceHolderText contains a bug in the default arguments. you have to set the 3 arguments at hand.
here you can find an old msdn discussion post from me with more details for the bug.
http://social.msdn.microsoft.com/Forums/office/en-US/0c03837b-aca1-4cb6-81b7-f4fac8f36a04/possible-bug-in-wordcontentcontrol?forum=worddev
*Sebastian
here you can find an old msdn discussion post from me with more details for the bug.
http://social.msdn.microsoft.com/Forums/office/en-US/0c03837b-aca1-4cb6-81b7-f4fac8f36a04/possible-bug-in-wordcontentcontrol?forum=worddev
*Sebastian