1) Enter part of or the full last name of the user you wish to share their line/extension with another user.
2) Click Search.
1) Select the Identity/Device Profile Name of the phone you wish to share this users line on.
2) For the Line/Port, use the User ID from above and add a _N at the end where N is a unique number. Ex: 0000100004_1010_1 (Note: if you need to share this line on multiple phones, you would follow these steps and increase N by 1, so the next could be 0000100004_1010_2 etc).
3) Click OK to save changes.
Reboot the phone selected in #1 and it will pull down the updated config displaying this shared line.