C:\Users\ice>gem install zookeeper
Temporarily enhancing PATH to include DevKit...
Building native extensions.  This could take a while...
ERROR:  Error installing zookeeper:
        ERROR: Failed to build gem native extension.

        C:/Ruby193/bin/ruby.exe extconf.rb
'.' is not recognized as an internal or external command,
operable program or batch file.
*** extconf.rb failed ***
Could not create Makefile due to some reason, probably lack of
necessary libraries and/or headers.  Check the mkmf.log file for more
details.  You may need configuration options.

Provided configuration options:
        --with-opt-dir
        --without-opt-dir
        --with-opt-include
        --without-opt-include=${opt-dir}/include
        --with-opt-lib
        --without-opt-lib=${opt-dir}/lib
        --with-make-prog
        --without-make-prog
        --srcdir=.
        --curdir
        --ruby=C:/Ruby193/bin/ruby
extconf.rb:49:in `safe_sh': command failed! ./configure --prefix=C:/Ruby193/lib/ruby/gems/1.9.1/gems/zookeeper-1.2.8/ext --with-pic --without-cppunit --disable-dependency-tracking  2>&1 (RuntimeError)

        from extconf.rb:71:in `block (2 levels) in <main>'
        from extconf.rb:67:in `chdir'
        from extconf.rb:67:in `block in <main>'
        from extconf.rb:53:in `chdir'
        from extconf.rb:53:in `<main>'
Building zkc.
tar xzf zkc-3.3.5.tar.gz 2>&1
./configure --prefix=C:/Ruby193/lib/ruby/gems/1.9.1/gems/zookeeper-1.2.8/ext --with-pic --without-cppunit --disable-dependency-tracking  2>&1


Gem files will remain installed in C:/Ruby193/lib/ruby/gems/1.9.1/gems/zookeeper-1.2.8 for inspection.
Results logged to C:/Ruby193/lib/ruby/gems/1.9.1/gems/zookeeper-1.2.8/ext/gem_make.out