I'm not sure when it was changed, but it was fairly recently. If you set the ctype of PCLN to STKM, it creates SPWN instead. It used to directly created STKM.
The problem with this is that the purpose of creating PCLN(STKM) instead of SPWN is to be able to turn it off. When it creates SPWN, you have to manually delete it to turn it off again.