Sun Jan 09, 2005: I fixed a bug that caused the test_rb program to
                  go into an infinite loop if the user entered an
                  invalid key.  Thanks to Amores Perros for pointing
                  out this problem.

Wed Sep 19, 2001: I fixed some bugs and memory leaks pointed out
                  by Brett Donahue and added some rudimentary
                  memory checking tests to the makefile.