wfSwservOutPhoneNumPlan 1.3.6.1.4.1.18.3.5.1.4.6.1.9

If Isdn and if type of number is UNKNOWN or INERNATIONAL or NATIONAL or SUBSCRIBER then a plan number is needed. UNKNOWN is 0 , using 16 (0x10)to satisfy MDL requirement. We will AND this field with 0x0F before using it.