  We discuss the possibility that fermions bind due to Higgs or pseudoscalar
exchange. It is reasonable to believe on qualitative grounds that this can
occur for fermions with a mass larger than 800-900 GeV. An exchange of a
pseudoscalar boson leads in the non-relativistic limit to an unacceptable
potential which behaves like 1/r^3 at the origin. We show that this singular
behaviour is smeared out when relativistic effects are included.
