AOB: the drop might be related to this filing: <A HREF="http://www.sec.gov/Archives/edgar/data/1090514/000101968706000490/aobo_424b3-030306.txt" target="_blank">http://www.sec.gov/Archives/edgar/data/1090514/000101968706000490/aobo_424b3-030306.txt</A> If that's the case, I think it's not bad to buy at lower 4s.