  We examine intrinsic interfaces separating crystalline twin domains of
opposite spin-orbit coupling in a noncentrosymmetric superconductor such as
CePt3Si. At these interfaces, low-energy Andreev bound states occur as a
consequence of parity-mixed Cooper pairing, and a superconducting phase which
violates time reversal symmetry can be realized. This provides an environment
allowing flux lines with fractional flux quanta to be formed at the interface.
Their presence could have strong implications on the flux creep behavior in
such superconductors.
