You get back gzip compressed content because ...

1. The server is able to compress the requested content on-the-fly (typically, because gzip_cnc or mod_gzip are installed), and
2. your user-agent said that it could handle gzip-compressed content ("Accept-Encoding" header)

or

1. The server is able to compress the requested content on-the-fly, and
2. the server does not care about the capabilities of the user-agent

In the first case, make sure that the announced and the real capabilities of your user-agent match, i.e. don't send "Accept-Encoding: gzip" if you can't or don't want to handle gzip-compressed content.

In the latter case, the server is misconfigured, either accidentally or intentionally. All currently and commonly used browsers can handle gzip compressed content, so not checking the capabilities at all save a few thousand CPU cycles and some lines of code. Of course, this is not what I would call a well-behaved server.

See also http://schroepl.net/projekte/mod_gzip/encoding.htm

Your eval "surprise" was already explained: eval traps die, nothing less, nothing more. It does not help you with code that exits or messes up perl's internal structures.

Alexander