"Does anyone know how to get around this, using perl cgi?"

If you have to use CGI I suggest using a templating module (Template, HTML::Template) to separate your Perl and HTML/CSS/JavaScript etc.

Create a HTML template which renders properly within the target browsers, then either populate it with perl generated content (sort of the point of templating systems), or use it as static HTML (your example here simply generates HTML, and doesn't populate any perl generated values), with the form action pointing to a perl script. In short, IMHO it's easier and less time consuming to create HTML without using CGI.