When I run the "curl" line and the script, I get exactly the same output, byte for byte (well, the script prepends a '200 OK', but otherwise identical):

  Polk North America Secure File Transfer

          Login
          Name:    [               ]
      Password:    [               ]

                    [Log In]

   Welcome to Secure File Transfer

   Polk North America Secure File Transfer is an enterprise file trans
+fer
   system -- leading the industry in security, reliability, performanc
+e,
   scalability, and extensibility.
[download]

(I've elided some whitespace in the above.) It seems that your script works fine; if you're having problems, they most likely lie elsewhere.

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