You make the reference to your imagemap file via a cgi-bin program. For instance if user maria has an imagemap file mymap.map in his public_html directory that he wants to link with somepicture.gif. To do this in his html file he would make the following reference:
<a href=http://www.dca.fee.unicamp.br/cgi-bin/imagemap/~maria/mymap.map>This would display the image somepicture.gif and have certain areas in it clickable as defined in mymap.map
<a img src=http://www.dca.fee.unicamp.br/~maria/somepicture.gif ismap >
</a>
