Cisco IOS Release 12.1(3)T

• Cisco IOS Release 12.1(3)XI

• Advanced Voice Busyout

• FXO Supervisory Disconnect Tone
  2600, 3600, MC3810 series

• T.38 Fax Relay for Voice over IP H.323

• Transparent Common Channel Signaling (T-CCS)

• Trunk Conditioning for FRF.11 and Cisco Trunks

• PSTN Fallback

• T1/E1 Alarm Conditioning for Switched Calls and Permanent Connection Trunks