  Complex parameters in the MSSM lead to mixing and interference between the
two heavier neutral CP-even and CP-odd Higgs states. These effects can become
very large in the case of almost degenerate states. In a CP-violating benchmark
scenario, we investigate phenomenological implications of such interferences in
view of the LHC searches for heavy Higgs bosons decaying to a pair of
$\tau$-leptons and produced in gluon fusion and in association with b-quarks.
Strongly destructive effects leave parameter regions unconstrained that would
be regarded as excluded if no interference terms were taken into account.
