File fields on 'On Behalf of' profiles cause javascipt to break.

When an organization has custom file fields having files already attached (custom values already present), the setDefaults function causes javascript to break due to code incorrectly setting a default value for the textbox.

Not allowing a value for a file field is basically a security measure that is implemented by the browser to prevent malicious code from stealing uploaded file information. Here is more about the subject: http://www.cs.tut.fi/~jkorpela/forms/file.html#value