Though wheat malt is usually blamed for causing haziness in beer, the same proteins that cause that haziness greatly increase mouthfeel and head retention.  Fortunately, a small amount of wheat malt contributes much more to head retention than to haziness.  With every batch of beer I make, I try to add between an ounce to a quarter pound of some sort of wheat malt (recently I have been using Victory Wheat).  The resulting beers end up with a long lasting crown without any noticeable differences in clarity.