Thanks to Andy and Blakem for their help. Following the link did not work, it seemed to return the same error as before. I was not able to get PUT or GET to work, something about a bad header.
The url I am posting to, /controlcenter/ is the action for the form I am submitting.
I did, however, notice something about the server's response. It said that the server is using HTTP 1.1. The documentation on CPAN for the LWP module says that "The libwww-perl HTTP implementation currently support the HTTP/1.0 protocol." So maybe that is the problem. I will look into it.