  Resonance width effects in charged $B$ decays to neutral $D$ mesons and
excited kaon states $K_i$ around 1400 MeV are shown to lead to large calculable
final state phases. $CP$ asymmetries are defined for any charged $B$ decay to
three pseudoscalar mesons involving intermediate overlapping resonance states.
Asymmetries up to about 10$\%$ are found in $B^+\to K^+_i D^0\to (K\pi)^+ D^0$.
Decay distributions can be used to determine the weak phase $\gamma$ of the
Cabibbo-Kobayashi-Maskawa (CKM) matrix. No separation of the contributions from
individual resonances is required.
