  We consider in this paper a Left-Right symmetric gauge model in which a
global lepton-number-like symmetry is introduced and broken spontaneously at a
scale that could be as low as 10^4 GeV or so. The corresponding physical
Nambu-Goldstone boson, which we call majoron and denote J, can have tree-level
flavour-violating couplings to the charged fermions, leading to sizeable
majoron-emitting lepton-flavour-violating weak decays. We consider explicitly a
leptonic variant of the model and show that the branching ratios for \mu ->
e+J, \tau -> e + J and \tau -> \mu + J decays can be large enough to fall
within the sensitivities of future \mu and \tau factories. On the other hand
the left-right gauge symmetry breaking scale may be as low as few TeV.
