The underlying cause of the cracks is the cement blocks move at one rate and the wood paneling move at a different rate. This is caused most often by two factors, Temperature and Humidity. You are not likely to do much about these items so the fix lies somewhere else.

This fix is simple but has some added cost. Available is a wallpaper liner which when installed over paneling allows for the moving of the wood under the wallcovering so as not to cause the surfaces to crack.

Generally, I recommend the liner to be installed horizontally on paneling so as to not allow the seams to coincide with the grooves in the paneling. You should be able to order the liner material at your local wallcoverings dealer.