Outlook 2000 shared folder

I am running Exchange 5.5 service pack 4. Outlook 2000 as the client. I have a folder in a mailbox in New York that I shared with serveral users in NY. They can access the folder fine. I attempt to share the folder with two users in LA and they can’t expand the folder. I made them a owner of the folder and I also tried making them a user of the mailbox. The LA postoffice is running on a separate box. We only have one site.