George, the cause is that gettext _() returns translation header information when an empty string is translated. A few such cases snuck into v8.0.06, and have been resolved in dev for v8.1.00. This should be released in the next 3 weeks (just waiting for Italian translation to be finished). In the meantime, just remove _() from the offending string: it prevents translation from working, but you are not dealing with any other languages, so should be fine.