Is it safe to eat mouldy bread?
In short, the answer is no, it is NOT safe.

http://www.cnn.com/2009/HEALTH/08/11/food.safety/index.html


  It's tempting to lop off the fuzzy
  patch, but the mold could have spread
  already.
  
  "Once you're able to see mold on
  bread, it means there's quite a lot of
  mold," said Nelken, a food consultant
  in Woodland Hills, California. "It's
  indicative that there's mold on other
  slices, just not at the level you can
  see it. Why jeopardize your health on
  a slice of bread?"
  
  Nelken likened mold to jellyfish.
  "Even though you scrape off the head
  of the jellyfish, the tentacles are
  still in the food product."
  
  Eating moldy bread could cause an
  upset stomach. Although most molds are
  innocuous, it's probably not going to
  taste good, food experts said. The
  U.S. Department of Agriculture Food
  Safety and Inspection Service
  recommends discarding moldy bread and
  baked goods, because of their porous
  texture.