Revision By field in Rev Table not filled in with new rev?

I am curious, we use Workgroup PDM 2012 and when a new revision is entered (using the built in feature) the table includes the date it is entered, the note entered in the check in but the By field is left blank.

How do i get the system to populate that field in the rev table?

Thanks,

Jeremiah

SolidworksWorkgroup Pdm