Our small house was probably built in the 40's or 50's as a summer cabin (900 square feet). We've lived in the home year-round for 32 years with white-washed tongue and groove knotty pine paneling in the living room as well as on the kitchen cabinets.

How can we paint the paneling white without the knots coming through? (It's not sheet paneling - it's the real stuff.) We tried to do this on some of the door trim using Kiln as a primer but the knots show through, leaving a dirty appearance.

Any suggestions?