onlyif not honored in Exec

gistfile1.pp

  exec {'Avoid multiple mcollectived':
    path    => '/usr/bin:/usr/sbin:/bin',
    command => 'pkill -f mcollectived',
    onlyif  => 'test `pgrep -f mcollectived | wc -l` -gt 1',
    notify  => Service['mcollective'],
  }

which version of puppet? I think I'm seeing the same 2.7.6

this now works:

class perdition::service::xinetd
{
  exec {
    'killperditiondaemon':
      path    => '/usr/bin',
      command  => 'pkill -f "[p]erdition.*: daemon"',
      onlyif  => 'pgrep -f "[p]erdition.*daemon"';
  }
}