If you double click an image in the WYSIWYG editor, and go to the advanced tab, there is a section called map. However, all this will do is place the name of the map in the <img> tag, it will not create the image map. This must be entered manually in to the HTML. For example, if you want to create the following map:

<img src="planets.gif" width="145" height="126" alt="Planets" usemap="#planetmap" />

<map name="planetmap">
  <area shape="rect" coords="0,0,82,126" href="sun.htm" alt="Sun" />
  <area shape="circle" coords="90,58,3" href="mercur.htm" alt="Mercury" />
  <area shape="circle" coords="124,58,8" href="venus.htm" alt="Venus" />
</map> 

You would enter #planetmap in to the WYSIWYG editor on the advanced tab when you double click an image. Then you would add the code for < map name="planetmap"> </map> in to the HTML editor manually by clicking "HTML" and putting that code somewhere inside, then clicking update.