安装 amarok 1.4.8是找不到ruby

安装 amarok 1.4.8时找不到ruby, 但是我已经安装了Ruby-1.9.1-p376。 我试着几个不同的版本都有这个问题。 这个问题困扰我很了，请大家帮帮忙。

checking for ruby... /usr/bin/ruby
checking ruby.h usability... no
checking ruby.h presence... no
checking for ruby.h... no
checking if amarok should be compiled... no


=== Amarok - ERROR ==========================================================
==========================
=
= The Ruby programming language is not installed. Please obtain Ruby
= (version 1.8 or later) from http://ruby-lang.org, or install a distribution
= package. To build Amarok requires the Ruby header files as well, which some
= distributions package separately.
=
==================================
=== AMAROK WILL NOT BE BUILT ================================================
==================================
=
= Some mandatory dependencies are either not installed or not installed
= correctly. See the Amarok README for help with this issue. Further assistance
= can be found at http://amarok.kde.org or in amarok on irc.freenode.net.
= You will still be able to build other modules from extragear/multimedia.
=
===============================================================================