There are too many to be listed on the margins of MO.

Look at the archives of the newsgroups
comp.soft-sys.math.maple, comp.soft-sys.matlab, 
sci.math.symbolic, comp.soft-sys.math.mathematica.
There you can find hundreds of bugs reported.

There is a notorious CAS bug hunter who once
maintained a bug list for Maple and shows
more than 5000 disturbing observations.
(Press the [Go!][1] button.) Or go to MapleSoft and search [Maple Primes][2].
 
Please don't shoot the messenger. 


  [1]: http://maple.bug-list.org/
  [2]: http://www.mapleprimes.com/search/node/bug