HTTP header 411 error in asp.net

I have .aspx file with some simple logic. This file can be accessed only using HTTP Post method. My problem is that in some registration form (regnow) they ask me to supply the url (my .aspx url) and the access method (Post or Get). I select the Post and then they try to access the url and get HTTP 411 error (header missing content-length).

Is there a way to prevent the web application from sending back this error? maybe some kind of configur开发者_C百科ation in the web.config file?

Thank you very much,

Adi Barda