Can't install mysql2

[pinpox]

Hi,

I'm having trouble installing the myusql2 gem in jruby running in rvm.
It seems that some header files are missing

          Fetching: mysql2-0.3.18.gem (100%)
Building native extensions.  This could take a while...
ERROR:  Error installing mysql2:
    ERROR: Failed to build gem native extension.

    /home/binaryplease/.rvm/rubies/jruby-1.7.19/bin/jruby -r ./siteconf20150221-30107-19z3q24.rb extconf.rb
/home/binaryplease/.rvm/rubies/jruby-1.7.19/lib/ruby/shared/mkmf.rb:14: Use RbConfig instead of obsolete and deprecated Config.
mkmf.rb can't find header files for ruby at /home/binaryplease/.rvm/rubies/jruby-1.7.19/lib/native/include/ruby/ruby.h

extconf failed, uncaught signal 1

Gem files will remain installed in /home/binaryplease/.rvm/gems/jruby-1.7.19/gems/mysql2-0.3.18 for inspection.
Results logged to /home/binaryplease/.rvm/gems/jruby-1.7.19/extensions/universal-java-1.8/1.9/mysql2-0.3.18/gem_make.out

I don't know if thats a jruby or a rvm issue, but it works with any other ruby implementation (MRI, rubinius)

Setup:
jruby-1.7.19 [ x86_64 ]
3.18.6-1-ARCH #1 SMP PREEMPT Sat Feb 7 08:44:05 CET 2015 x86_64 GNU/Linux