Illustrate error handling for function defined in eval() but called in normal code.

1. Load javascript file via XMLHttpRequest
2. eval() it.
3. Call the function prod(animal) three times, two correct, one error.
4. error when the function prod(animal) is called with no argument.

01/2007 Works in Firebug 1.1b9 and Fireclipse:

1. Halts on error, positions Script tab to line of error call (animal.say())
2. Console tab reports error ("animal has no properties") and source line of error ("animal.say()") correctly.
3. Console tab error message links to stack with two entries, "prod(undefined)" and "__top_level__()".
4. Both entries in stack are linked to correct source lines in Script tab window
5. Javascript console reports error against data: url buffer on correct line