While doing a mass mailbox move from one exchange provider to us i found this handy tool. It allows you to bulk import PST files directly to exchange with no outlook installed.
PST Capture helps you search your network to discover and then import .pst files across your environment – all from a straightforward admin-driven tool. PST Capture will help reduce risk while increasing productivity for your users by importing .pst files into Exchange Online or Exchange Server 2010 – directly into users’ primary mailboxes or archives.
http://www.microsoft.com/en-us/download/details.aspx?id=28767
