I want to change first line of header, modifying the method and/or URL.
The (excellent) Tamperdata firefox plugin allows a developer to modify the headers of a request, but not the URL itself. This latter part is what I want to be able to do.
So something like...
GET http://foo.com/?foo=foo HTTP/1.1
... could become ...
GET http://bar.com/?bar=bar HTTP/1.1
For context, I need to tamper with (correct) an erroneous request from Flash, to see if an error can be corrected by fixing the url.
Any ideas? Sounds like something that may need to be done on a proxy level. In which case, suggestions?