What do you mean by this one?
I guess they call it the Microsoft Exchange Global Address List (GAL.)
It's the global company contacts directory on the exchange server. From the iPhone you can (remotely) search the list (over the internet on the server) and look up contacts. Once you find one you can use that contact to send email, phone call, or SMS. But you're unable to "copy" that contact to your local contacts (contacts that reside locally on your phone which you sync back to YOUR exchange/outlook profile.)
On Windows mobile, if you did this (looked up a contact on the GAL) then when you found it you could simply add it to your contacts so you don't have to look it up again.
However, to the iPhone's credit, when you start to author an email, it automatically searches the GAL as you type a name, so it treats the GAL contacts in much of similar way as if they were on your phone. Except it won't work with Caller ID, etc.
If you want to add that person's contact info to your contacts, you have to do it in Outlook on your computer, or manually enter it on the phone.
I was just stating that this is one of the many 'little' features that you can't do on the iPhone that you could on Windows Mobile. And it really irritates some people who used this feature and are now missing it.
Here's the excerpt from the iPhone User Guide which describes this:
"Searching Contacts
You can search the first, last, and company names in your contacts on iPhone. If you have a Microsoft Exchange account set up on iPhone, you may also be able to search your enterprise Global Address List (GAL) for contacts in the organization. When you enter search information, contacts with matching information appear immediately as you start to type.
Search contacts: In Contacts, tap the search field at the top of any list of contacts and enter a first, last, or company name.
Search a GAL: Tap Groups, tap Directories at the bottom of the list, then enter a first, last, or company name.
You can?t edit GAL contacts or save them to iPhone."
For more, in the iPhone User Guide's index:
GAL (Global Address List) 47, 98, 138"
iPhone User Guide:
Apple - Support - Manuals