We consider new s-channel scalar exchanges in e+e- -> ZZ,W+W- in supersymmetry with a small lepton number violation. We show that a small bilinear R-parity violating term which leads to sneutrino--Higgs mixing can give rise to a significant scalar resonance enhancement in e+e- -> ZZ,W+W-. We use the LEP2 measurements of the WW and ZZ cross-sections to place useful constraints on this scenario. We also find, under conservative assumptions on the relevant parameter space involved, that such an exchange of the sneutrino-like admixture in e+e- -> ZZ,W+W- may be accessible to a 500 GeV e+e- collider.