Because CUC does not have a native interface with Gmail, the only interface you could get natively, is accept and relay to Gmail (or any other) accounts
There are 3rd party options for this, you would need to discuss with them if Speechview was tested
http://docwiki.cisco.com/wiki/CUC_FAQ#Can_I_integrate_with_Gmail_.2F_Zimbra_for_SIB_.2F_UM.3F.3F
HTH
java
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