I'm trying to price an open jaw journey to Oz next year. LHR - PER (March 09), SYD - LHR (April 09).
I can book the LHR - PER leg, but the booking engine says: -
Sorry we were unable to find flight options for the number of passengers requested. Please select new dates and try again - regardless of which cabin I choose (I even tried e..., no can't say it!

).
Could this be something to do with the A380 deliveries falling behind a little? Or are they just thinking up a new low price First fare?