Vinegar in the Dishwasher

This was part of an e-mail I received from my mother-in-law awhile back.  Once again, love vinegar.

... she (my sister in law) fills the rinse dispenser in her dishwasher with white vinegar instead of the expensive products made for that purpose. So I decided to try it when it was empty. I have filled it twice now and it lasts as long as the purchased product and I haven't noticed any deterioration in the way the glassware come out. I don't know how that little amount of vinegar could have any effect, but it seems to be okay. I have also carefully poured vinegar in the holes in the sprayer arms when it looks like they might be getting clogged with mineral deposits and let it soak until the next time I run the dishwasher. I guess it helps!