Moore describe Kallima buxtoni in 1879 from Sumatra not Borneo.
Funet's entry was taken from 'Butterflies of the Oriental Region' by D'Abrera published in 1986. ( BOR )
C&P4 1992 supercedes that & it list K. limborgi as distributed from Burma to Neomalaya ( Sumatra, Malaya, Borneo ).
In many instances, Sumatra & Borneo shares the same subspecies that is different from Malaya, eg. P. aristolochiae, P. nephelus.
I would stick to K. limborgi buxtoni unless there is recent news.
TL Seow:cheers: