10.5.3_SP7.1 - An Overview of Features
F-5533 T.38 Support when using AMR codec
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With the addition of feature F-5533, the IMG 1010 and IMG 1004 now supports the AMR codec when negotiating for T.38 fax support. The AMR Codec now supports all the same fax capabilities as any other codec when a transition to fax mode is being negotiated.