  We present the timing of the first five millisecond pulsars discovered in the
globular cluster Omega Centauri and the discovery of a pulsar with a spin
period of 3.68 ms. With a timing baseline of $\sim$3.5 yr we are able to
measure the derivative of the spin frequency ($\dot{\nu}$) for the first five
pulsars. Upper limits on the pulsar line-of-sight acceleration are estimated
and compared with predictions based on analytical models of the cluster. We
find that PSRs J1326$-$4728B and D show large negative accelerations, which are
in tension with the minimum acceleration predicted by analytical models. We
searched for pulsed $\gamma$-ray signals using 14.3 yr of data from the Fermi
Large Area Telescope. Although we found no evidence for $\gamma$-ray
pulsations, PSRs~J1326$-$4728A, B, C and E are associated with X-ray sources.
This suggests that the observed $\gamma$-ray emission from Omega Centauri is
likely caused by the emission of the ensemble of MSPs. Finally, the linearly
polarised emission from PSR J1326$-$4728A yields a rotation measure of
$-18\pm8$ rad m$^{-2}$.
