forms need a start tag?

Hello,

I am trying to correct this page:
http://lysanne.net/CVS_CSS/maquette/index.htm

I am getting an error message which I do not understand:
Line 37, column 60: document type does not allow element "FORM" here;
missing one of "OBJECT", "MAP" start-tag
<form action="#" method="get" name="langue" id="langue">

I have not found anywhere in the html 4.01 specs. that forms need to be
enclosed in an "object" or "map" tag. Or does this error mean something
else?

I would greatly appreciate help on this.

Thank you,
Lysanne