An Anchor Mobile Switching Center emulation (MSCe) and a Target MSCe are described herein that take part in an intersystem handoff of a Mobile Station (MS) which is in communication with a B-party. Upon the MS establishing a connection with the Target MSCe, the Anchor MSCe may perform SDP offer/answer exchange between the Target network and the B-Party for the purpose of codec renegotiation to correct a transcoding incompatibility or to enhance the voice bearer path characteristics or to minimize the number of transcodings in the bearer path, between the two parties. The Anchor MSCe and the Target MSCe both support Advanced Legacy Mobile Station Domain (ALMSD) implying that only the SIP transport is used for intersystem handoff communications.
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