callto:servername/e-mail address
For example, to author a call link on your Web page, you could insert the following text to make a link from the address uls.microsoft.com/cgray@mydomain.com:
Call me using Microsoft NetMeeting at
<A href="callto:uls.microsoft.com/cgray@mydomain.com">
uls.microsoft.com/cgray @mydomain.com</A>