Building native extensions.  This could take a while...
ERROR:  Error installing mssql:
    ERROR: Failed to build gem native extension.

        /Users/jeffsmykil/.rvm/rubies/ruby-1.9.3-p327/bin/ruby extconf.rb
checking for iconv_open() in iconv.h... no
checking for iconv_open() in -liconv... yes
checking for sybfront.h... no
-----
freetds is missing.
-----
*** 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
    --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=/Users/jeffsmykil/.rvm/rubies/ruby-1.9.3-p327/bin/ruby
    --enable-lookup
    --disable-lookup
    --with-iconv-dir
    --without-iconv-dir
    --with-iconv-include
    --without-iconv-include=${iconv-dir}/include
    --with-iconv-lib
    --without-iconv-lib=${iconv-dir}/lib
    --with-freetds-dir
    --without-freetds-dir
    --with-freetds-include
    --without-freetds-include=${freetds-dir}/include
    --with-freetds-lib
    --without-freetds-lib=${freetds-dir}/lib
    --with-iconvlib
    --without-iconvlib


Gem files will remain installed in /Users/jeffsmykil/.rvm/gems/ruby-1.9.3-p327/gems/tiny_tds-0.5.1 for inspection.
Results logged to /Users/jeffsmykil/.rvm/gems/ruby-1.9.3-p327/gems/tiny_tds-0.5.1/ext/tiny_tds/gem_make.out