Smeared products frequently result from too much DNA template.
A good indication of this is if you use up the primers (i.e.,
can't see 'em at the end).
Do a quick template determination.
If this doesn't work try adding 10% DMSO to the reaction.
Mark E. Siddall "I don't mind a parasite...
mes at vims.edu I object to a cut-rate one"
Virginia Inst. Marine Sci. - Rick
Gloucester Point, VA, 23062