Building gem with native extension

Dear all,

I can not install a gem that has a native extension and ran into this

jruby -S jgem install datamapper

JRuby limited openssl loaded. gem install jruby-openssl for full
Building native extensions. This could take a while…
ERROR: Error installing datamapper:
ERROR: Failed to build gem native extension.

jruby.bat.exe extconf.rb install datamapper
‘jruby.bat.exe’ is not recognized as an internal or external command,
operable program or batch file.

Has anyone able to solve this kind of problem before?

Best regards,

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check the thread i posted about libxml. Apparently anything built with
native C extensions without a java port will not work with Jruby.
Here is a quote from the wiki:

"Many Gems will work fine in JRuby, however some Gems build native C
libraries as part of their install process. These Gems will not work in
JRuby unless the Gem has also provided a Java equivalent to the native

Mongrel and Hpricot are two examples of Gems that build their native
in a platform independent manner. Each of them specify a parsing library
using the Ragel language and a Ragel program can be automatically
into either C or Java as part of the compile process.

Also, keep in mind that installing gems from behind a firewall will
setting the HTTP_PROXY (format http://


On Wed, Jun 18, 2008 at 10:27 PM, Partogi, Joshua
[email protected]