We spoke with Cypress and they are aware of this bug planning a fix for around the end of June 1995. This only occurs when MegaPhone tries to forward a call to PowerTalk on a network with no Zones (the '*' zone) in the Chooser. You can put a router on the network.
If you need demonstrate MegaPhone and PowerTalk, try this: Do not use the Universal Mailbox to get mail on networks with no zones, and pre-load the mailbox with voice messages prior to running the demo on a zone-less network.
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