  We discuss the impact of the recent KamLAND constraint on the solar
anti-neutrino flux on the analysis of solar neutrino data in the presence of
Majorana neutrino transition magnetic moments and solar magnetic fields. We
consider different stationary solar magnetic field models, both regular and
random, highlighting the strong enhancement in the anti-neutrino production
rates that characterize turbulent solar magnetic field models. Moreover, we
show that for such magnetic fields inside the Sun, one can constrain the
intrinsic neutrino magnetic moment down to the level of mu_nu lessthan few
times 10^-12 x mu_B irrespective of details of the underlying turbulence model.
This limit is more stringent than all current experimental sensitivities, and
similar to the most stringent bounds obtained from stellar cooling. We also
comment on the robustness of this limit and show that at most it might be
weakened by one order of magnitude, under very unlikely circumstances.
