Dear Scott,

     There is an animal dip available called Permethrin (I buy it as a
3.5% solution) which I have used as a repellant on clothes while
traveling in Africa.  I got the idea from a bird watcher who gave me an
article out of a birder magazine.  Seens the military tested it and found
that a 0.5% sloution sprayed on clothes was effective for up to a year,
even through a number of army launderings.  If you are interested I will
try to find the article and send you more particulars.

Jerry in PA