  In this paper we use a generalized version of a method originally proposed by
Holz and Wald to investigate the effects from gravitational lensing on Type Ia
supernovae measurements. We find that results for different mass distributions
in smooth dark matter halos are very similar, making lensing effects
predictable for a broad range of density profiles. Also, a sample of 100
supernovae at z = 1, should be sufficient to discriminate between the case of
all dark matter in smooth halos and the extreme case of all dark matter in
point-like objects.
