jtreg should return an error code if the -bug:<bugid> options is used and no tests are found, whereas the return value of 0 incorrectly indicates a success (leading to the interpretation that tests were found and run successfully).
Something like:

/** No tests were found. */
    public static final int EXIT_NO_TESTS = 6;

This would facilitate better automated bug verification.

work-arond is to grep results directories for tests found or not tests found message.