I faced the same problem even with different version, see below
best,
fatmah
C:>ruby -v
ruby 1.8.6 (2007-03-13 patchlevel 0) [i386-mswin32]
C:>gem install webgen
Need to update 44 gems from http://gems.rubyforge.org
…
complete
Install required dependency cmdparse? [Yn] y
Install required dependency RedCloth? [Yn] y
ERROR: While executing gem … (Zlib::BufError)
buffer error
----- Original Message ----
From: Gilbert R. [email protected]
To: ruby-talk ML [email protected]; [email protected]
Sent: Friday, June 29, 2007 8:40:01 PM
Subject: Re: [ANN] webgen 0.4.5
Hi, Thomas
Thomas L. wrote:
Hey everybody!
I just release a new webgen version which fixes some bugs and brings one
that’s good news 
i wanted to install the new version immediately,
but with =
C:\WINNT\system32>ruby -v
ruby 1.8.5 (2006-08-25) [i386-mswin32]
it gave me =
C:\WINNT\system32>gem install webgen
ERROR: While executing gem … (Zlib::BufError)
buffer error
Regards, Gilbert
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