-------------------- untied hash works fine
k='unt_b' v='22'
k='unt_a' v='11'
-------------------- tied hash returning each's return directly works fine
TIED_HASH_1 FIRSTKEY scalar
k='t_1_b' v='22'
TIED_HASH_1 NEXTKEY scalar
k='t_1_a' v='11'
-------------------- tied hash returning its own list is brok
TIED_HASH_2 FIRSTKEY scalar
x='t_2_b' y='22'
k='22' v='undef'
TIED_HASH_2 NEXTKEY scalar
x='t_2_a' y='11'
k='11' v='undef'