Problem installing Onigurama on Ubuntu

If you are getting below while installing oniguruma 1.1.0 on Ubuntu

Installing ri documentation for oniguruma-1.1.0...

No definition for oregexp_initialize
Installing RDoc documentation for oniguruma-1.1.0...

No definition for oregexp_initialize

just get it from here
http://rubyforge.org/frs/?group_id=3289&release_id=11612