PMD plugin 1.6 produces duplicate results. For a given module on the PMD Result
screen at http://hudsonurl/buildname/buildnumber/pmdResult, we'll see in the
table (for example):

Module, Total, Distribution
ModuleName, 2, (Bar graphic)
ModuleName-1, 2 (Bar graphic)

Where ModuleName-1 is an exact duplicate of the info in ModuleName. It produces
trend numbers 2x larger than expected, and of course duplicate data in general.

The total warnings at the top is 4, not two. The -1 after ModuleName in the
second row changes for each build. I've seen it be -1, -3, and -4. I haven't
seen a pattern yet.

I looked inside the target directory on the Hudson server and I see only one
result file for each of these builds where the PMD plugin produces duplicate
results.