p01-contact : simply add contact forms in your pages

[Donuts]

Hi, great plugin!
But I also need an option for a "file upload" like: http://cgi-lib.berkeley.edu/ex/fup.html. Its a sample file upload form.
I noticed that there was an file option in p01-contact.php.

Code:

/**
     * Return the general type of a field, even of specials fields.
     */
    function general_type()
    {
        $types = array(
            'name'    => 'text',
            'email'   => 'text',
            'phone'   => 'text',
            'website' => 'text',
            'subject' => 'text',
            'address' => 'textarea',
            'message' => 'textarea',
            'file'    => 'file',
            'captcha' => 'captcha',
            'askcopy' => 'checkbox');
        if(isset($types[$this->type]))
            return $types[$this->type];
        else return $this->type;
    }

So I thought I could do something simple like:

Code:

(% contact : name!, email!, file "File upload:",captcha! %)

But that does not work as I expected.
So what am I doing wrong? Help is appreciated. Greetings, Tom.