Crashes when loading XML with duplicate edges

[GoogleCodeExporter]

What steps will reproduce the problem?
1. Write an XML file that includes edges.
2. Either, include an edge <record source="a" destination="b" /> where both a = 
n and b = n.
3. Or, include two edges <record source="a" destination="b" /> once with a = n 
and b = m, 
and once with a = m and b = n.

What is the expected output? What do you see instead?

I expect an error message, but ggobi just crashes.

What version of the product are you using? On what operating system?

Version 2.1.8, under Windows.

Please provide any additional information below.

Original issue reported on code.google.com by akuhnp...@gmail.com on 19 Jul 2009 at 8:32