If you want to perform an ab-initio docking run with haddock you have two options (if no info available for both proteins):
1) Use the Center of mass restraints (expert/guru interface -> distance restraints menu).
2) Use the Random patches option which randomly selects a solvent accessible residue on each protein and defines a patch around those. Those become the active residues for that model (expert/guru interface -> distance restraints menu)
Option 2 is probably better if your molecules are highly anisotropic in shape. In both cases do increase the sampling to say 10000 models for it0 and 400 for it1 and water.
In case you do have info for one molecule but not for the other, a better strategy is to define on the second molecule all solvent accessible residues as passive.