Incidentally I was looking at this bug in the morning and it looks like this one is on the edge. Looks like we may not need the functionality as provided by the patch.

The existing headers are set in "FieldStorage" for use within the FieldStorage class. We do not need to get the headers out from environ variable and set in the FieldStorage headers. That is because we can already send the headers if we want as headers and environ are set by the users when Initializing FieldStorage object. 
So, I am really not sure of the utility value of the patch and gravitating towards closing this as Invalid. I am extremely sorry that this bug has been open for such a long time. But it also shows that not many have felt the need for this.