To send UCIDs over ISDN trunks, ensure that the field option in the ISDN-PRI or ISDN-BRI Trunks field on the System-Parameters Customer-Options screen is y.
Procedure
At the command prompt, type change trunk-group xxx, where xxx is the number of the trunk group. Press Enter.
In the Group Type field on the Trunk Group screen, select ISDN or SIP.
In the Supplementary Service Protocol field, select b for QSIG or other field options for User-to-User (UUI). This field is applicable with ISDN trunks.
In the UUI IE Treatment field for ISDN trunks or the UUI Treatment field for SIP trunks, select shared.