在Exchange 2003上创建大量邮箱

I've got around 750+ users that I'm going to create mailboxes for. Should I sleep for a bit between creates to not overload the exchange server or does it not matter? I've read that the actual mailbox is not created until the user accesses it or they get mail. I'm using CDOEXM and DirectoryServices in .NET 2.0.I've got around 750+ users that I'm going to cr