DECAY OF Z INTO 3 PSEUDOSCALAR BOSONS

We consider the decay of the Z boson into three pseudoscalar bosons in a general two-Higgs-doublet model. Assuming m(A) to be very small, an d that of the two physical neutral scalar bosons h(1) and h(2), A only couples to Z through h(1), we find the Z-->AAA branching fraction to be negligible for moderate values of tan beta drop upsilon(2)/upsilon( 1) if there is no lambda(5)(Phi(1)(+)Phi(2))(2)+ H.c. term in the Higg s potential; otherwise there is no absolute bound but very large quart ic couplings (beyond the validity of perturbation theory) are needed f or it to be observable.