Mirror modifier in sculpt mode?

Hello, I made a mesh face following one of Jonathan Williams tutorials. I am at the stage where I should start sculpting it. I am using Blender 2.5

I left the mirror modifier on (ie did not apply it) so that I only had to do the sculpting on half. Now in sculpt mode, the other half keeps turning invisible. I have to click the little eye in the mirror modifier section of the properties panel after any touch of the sculpting tool to make the mirrored half visible again. It’s really annoying. I am also using a 2-level multiresolution modifier on the mesh.

  1. Can I work in sculpt mode with the mirror modifier without applying it?
  2. How do I keep it displaying without interruption.

Thank you.