owp.cron error

Hi

I started see following error. Any idea why I'm getting this?

OS: CentOS 6
Kernel: 2.6.32-042stab123.3

Error message:
/etc/cron.daily/owp.cron:

/usr/lib64/ruby/gems/1.8/gems/rake-10.4.2/lib/rake/rdoctask.rb:4: ERROR: 'rake/rdoctask' is obsolete and no longer supported. Use 'rdoc/task' (available in RDoc 2.4.2+) instead. (RuntimeError)
from /usr/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:31:in gem_original_require' from /usr/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:31:in require'
from /opt/ovz-web-panel//script/cron_runner:11