  The beam spin asymmetry (BSA) in the exclusive reaction ep->ep pi0 was
measured with the CEBAF 5.77 GeV polarized electron beam and Large Acceptance
Spectrometer(CLAS). The xB, Q2, t and phi dependences of the pi0 BSA are
presented in the deep inelastic regime. The asymmetries are fitted with a
sin(phi) function and their amplitudes are extracted. Overall, they are of the
order of 0.04 - 0.11 and roughly independent of t. This is the signature of a
non-zero longitudinal-transverse interference. The implications concerning the
applicability of a formalism based on generalized parton distributions, as well
as the extension of a Regge formalism at high photon virtualities, are
discussed.
