How to integrate Perl with ASP.NET Webforms?

I want to integrate some existing Perl code with ASP.NET. I see many examples of accessing Perl from .NET, but nothing to the contrary. Has anyone had any experience trying to do this, or is everyone just re-creating their existing Perl functions in one fell swoop?

For more details, I have some functionality already implemented in Perl that we want to integrate with the large portal that we have implemented in ASP.NET Web Forms. Rather than reimplementing existing functionality in .NET, we want some of the portal pages to render through Perl (allowing it to access WebForm session information without putting it in a cookie). In the future, each new code and updates to Perl code will be implemented in .NET on an individual basis.