  We propose a model for the recently discovered Theta^+ exotic KN resonance as
a novel kind of a pentaquark with an unusual color structure: a color triplet
(ud) diquark, coupled to a color anti-triplet (ud s-bar) triquark in a relative
P-wave. The state has J^P=1/2^+, I=0 and is an antidecuplet of SU(3)_f. A rough
mass estimate of this pentaquark is close to experiment.
