The preliminary results of PIBETA experiment strongly suggest the presence of
non V-A anomalous interactions in the radiative pion decay. Without a guiding
idea about the nature of these new interactions it is very difficult to
interpret and fit experimental data. We assume that they arise as a result of
the exchange of new intermediate chiral bosons which interact anomalously with
matter. Their mixing with W-bosons leads effectively to a small anomalous weak
moment for W. Based on these assumptions, we show that the most general form of
the radiative pion decay rate can be parametrized by three new coupling
constants of the anomalous interactions.Comment: 7 pages, no figure