That might explain the 1.5 hour times, but some explanation of the 6 min WUs is what I'm interested in. The only times we've ever seen things like that was when:
a) Only "sweet" WUs are being crunched,
b) CPU/memory has been over-clocked too much,
c) Someone is intentionally submitting fraudulent work units
Obviously, I'd like to believe this is either A or B. 😉