[RndTbl] weird cert problem

Does anyone else get a cert error on this site: https://taxcess.gov.mb.ca/ It's invalid in Firefox (latest F19 version: 33.1, just came out today) on Linux. But it works ok on Chrome in Windows. Chrome shows the cert is brand new this month (I had never had a problem with their site before). Weird that a trust-validated site like that would have cert problems, unless they chose a no-name CA? Unless someone is MitM'ing me...