Failed to build gem native extension.(mysql)

I'm trying to install the mysql gem. I have mysql up and running,
everything is up to date through yum.

[root@localhost ~]#
[root@localhost ~]# gem install mysql -y
Select which gem to install for your platform (i386-linux)
1. mysql 2.7.3 (mswin32)
2. mysql 2.7.1 (mswin32)
3. mysql 2.7 (ruby)
4. mysql 2.6 (ruby)
5. Skip this gem
6. Cancel installation

3

Building native extensions. This could take a while...
ERROR: While executing gem ... (Gem::Installer::ExtensionBuildError)
    ERROR: Failed to build gem native extension.

ruby extconf.rb install mysql -y
can't find header files for ruby.

Gem files will remain installed in /usr/lib/ruby/gems/1.8/gems/mysql-2.7
for inspection.
Results logged to /usr/lib/ruby/gems/1.8/gems/mysql-2.7/gem_make.out
[root@localhost ~]#
[root@localhost ~]# cat /etc/fedora-release
Fedora Core release 6 (Zod)
[root@localhost ~]#
[root@localhost ~]# date
Sun May 13 08:01:18 BST 2007
[root@localhost ~]#
[root@localhost ~]#

thanks,

Thufir

From FC6 (fedora), this is how the mysql gem is installed?

[root@localhost ~]#
[root@localhost ~]#
[root@localhost ~]#
[root@localhost ~]# yum -y install ruby-mysql.i386
Loading "installonlyn" plugin
Setting up Install Process
Setting up repositories
Reading repository metadata in from local files
Parsing package install arguments
Nothing to do
[root@localhost ~]# yum search 'ruby-mysql'
Loading "installonlyn" plugin
Setting up repositories
Reading repository metadata in from local files

ruby-mysql.i386 2.7.1-2.fc6
extras
Matched from:
ruby-mysql

ruby-mysql.i386 2.7.1-2.fc6
installed
Matched from:
ruby-mysql
You have new mail in /var/spool/mail/root
[root@localhost ~]#
[root@localhost ~]# date
Sun May 13 20:10:19 BST 2007
[root@localhost ~]#

thanks,

Thufir