I'm not sure what the source of the problem is here, but a student is getting their submission suspended; the stderr that is included in the email to the administrator says only
ant BUILD FAILED unexpectedly. at
/home/misc/webcat//UserScripts/Knox/admin/JavaTddPlugin/execute.pl line 668.
This is after it apparently completes its analysis; at least, the full analysis appears in the diagnostic email to the administrator. (The actual student submission had some compiler errors, but those are not the source of the build problem; when I manually fixed the compiler errors, the Ant build still fails.) The student does not, however, have access to any of this information, just the administrator.
Attached are a submission and reference tests to generate the problem, and the associated ant.log file. The static checks (pmd and checkstyle) are both -none for this submission.