This amendment to the ISUP Specification ITU-T Rec. Q.1902.4 (07/2001) contains seven modifications:

1)��������� Correction of a cut and paste error in 7.4.1 and 7.4.4;

2)��������� Modifications of the codec negotiation in 8.3;

3)��������� Fallback procedures modification of 8.6.2.2.2;

4)��������� Signalling procedures for automatic rerouting (crankback); new procedures in a new clause 8.21;

5)��������� Procedures to support the calling party's category for calls from mobile terminals; new procedures in a new clause 8.22;

6)��������� Handling of national use elements at an international gateway SN or CMN; new procedures in a new clause 13.8;

7)��������� Two message flows examples in codec negotiation and modification in Appendix I.