Cisco Cisco IOS Software Release 12.4(6)T

 lists the release history for this feature.

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specific command, see the command reference documentation.

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 lists only the Cisco IOS software release that introduced support for a given feature in a given 

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software release train also support that feature.

Packet Mode Services on D Channel

12.4(6)T

This feature allows Japanese and European telephone 
switches to query Cisco routers for the availability of packet 
mode services on the ISDN D channel, in compliance with 
International Telecommunication Union (ITU) 
specification Q.931. 

The following sections provide information about this 
feature: 

The following command was modified by this feature: isdn 
x25 dchannel.