  The Bethe-Salpeter equation is combined with the temperature-cutoff
functional renormalization group approach to analyze the order parameter
structure for the leading instabilities of the 2D t-t' Hubbard model. We find
significant deviations from pure s-, d-, or p-wave forms, which is due to the
frustration of antiferromagnetism at small and intermediate t'. With adding a
direct antiferromagnetic spin-exchange coupling the eigenfunctions in the
particle-hole channel have extended s-wave form, while in the particle-particle
singlet pairing channel a higher angular momentum component arises besides the
standard d-wave symmetry, which flattens the angular dependence of the gap. For
t' closer to 1/2 we find a delicate competition of ferromagnetism and triplet
pairing with a nontrivial pair-wavefunction.
