That's not supported on the iPhone. Unlike Windows Mobile (and Blackberry) which allow you to create MEETINGS with attendees, iPhone only allows you to create calendar events/appointments for yourself (not meetings.)
It is one of the strong criticisms of Apple's implementation of Exchange on on the iPhone, namely that it's only partially implemented.
Just some of the Exchange features iPhone doesn't support:
1) Create or change meetings with attendees (you can only accept and change your alert.)
2) Contact and Calendar categories. It supports multiple contact and calendar folders, but not categories in each folder, like Windows Mobile.
3) No support for the To Do list/syncing.
4) No support for auto-syncing sub-folders with exchange. You can only manually sync folders. Only the inbox will push/sync automatically.
5) When searching/finding contacts on the exchange server directory, you can not add them to your local/personal contacts (you can on Windows Mobile.)
The list goes on. They did a pretty good job of an end-user implementation of exchange. But if you're the type of person that needs to schedule meetings from the phone, it's not (yet) designed to support you.
Despite Apple's marketing. This is not a business device yet. It's a consumer device that can get your work email/calendar/contacts.
Sorry for the bad news. We can only pray for improved support.
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:
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"
Interesting, I didn't even know you could search the GAL from the iPhone. I did hear that with Exchange 2007 you could do a search for mail which includes mail that isn't downloaded to the phone because the search actually takes place server side.