Description:
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Downloading the bz2 zipped version of the manual[1] sends a wrong HTTP header, which causes Internet Explorer to save the file as manual.tar.tar.
This is the wrong header that is send during this process is the.

Content-Type: application/x-tar

Ths .bz2 file is not a tar file at all, but a bz2 file :)

[1] http://pear.php.net/distributions/manual/pear_manual_en.tar.bz2


Reproduce code:
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Download http://pear.php.net/distributions/manual/pear_manual_en.tar.bz2


Expected result:
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Have IE save the file as pear_manual_en.tar.bz2

Actual result:
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IE saves the file as pear_manual_en.tar.tar