Booking a K and S fare online

Has anyone worked out how to get a K fare for one leg and an S fare for the return leg booked online?

This sometime happens when I book but I cannot find a way of getting this to work reliabily. Even when all the fares are availible.

Thanks

[Neil]

Its very hard using the Online system as you cannot select a specific fare code only the lowest/flexible option, the only thing you can really do it to ring Flying Club up and they will be able to give you the prices/book the flights for you.

Neil