multipage multipart/form-data form

I use script from http://www.asp101.com/samples/wizard.asp to create multipage form, and script works just fine. Problem is that my form have to be multipart/form-data because I have to upload an image too. The above example doesn't work when form is multipart/form-data.

I am using Persits ASPUPload component for image upload. Can anyone help me to adjust that script to work with multipart/form-data form.

Thank you very much
Tjodalv