  We propose a model for the longitudinal polarization of Lambda baryons
produced in deep-inelastic lepton scattering at any xF, based on static SU(6)
quark-diquark wave functions and polarized intrinsic strangeness in the nucleon
associated with individual valence quarks. Free parameters of the model are
fixed by fitting the NOMAD data on the longitudinal polarization of Lambda
hyperons in neutrino interactions. Our model correctly reproduces the observed
dependences of Lambda polarization on the kinematic variables. Within the
context of our model, the NOMAD data imply that the intrinsic strangeness
associated with a valence quark has anticorrelated polarization. We also
compare our model predictions with results from the HERMES and E665 experiments
using charged leptons. Predictions of our model for the COMPASS experiment are
also presented.
