[This is preliminary documentation and subject to change.]
| Common-Name=Extension-Name | Admin-Display-Name=Extension-Name |
| Admin-Description=Extension-Name | Object-Class=Attribute-Schema |
| Attribute-ID=1.2.840.113556.1.2.227 | OM-Syntax=64 |
| Attribute-Syntax=String(Unicode) | LDAP-Display-Name=extensionName |
| Multi-valued | System-Only=FALSE |
| Mapi-ID=\x80A9 | |
| Range 1 to 255 | |
| Schema-ID-GUID={bf967972-0de6-11d0-a285-00aa003049e2} | Comment=used by Exchange |