  The resonance states of $^{4}H$, $^{4}He$ and $^{4}Li$, embedded in the
three-cluster $d+N+N$ continuum, are investigated within a three-cluster model.
The model treats the Pauli principle exactly and incorporates the Faddeev
components for proper description of the boundary conditions for the two- and
three-body continua. The hyperspherical harmonics are used to distinguish and
numerate channels of the three-cluster continuum. It is shown that the
effective barrier, created by three-cluster configuration $d+N+N$, is strong
enough to accommodate two resonance states.
