Hi,
I must admit, I am not certain about this question, but here are a few thoughts.
Firstly, are you planning to import PSTs using the Import-Mailbox command? If so then you will need to wait until SP1 is released for that functionality.
Have you considered looking at the Quest Migration tools instead which may give more flexibility?
I wonder whether you could investigate the use of the -targetfolder switch. This is something I have only used on the export-mailbox command but wonder whether it could help in this case.
Sorry not to be more specific but hope it gives at least some help.
Cheers
Nathan
Nathan Winters - MVP Exchange Server
MCSE & MCSA 2000 & 2003 + Messaging, MCITP Exchange 2007, MCP, VMWare VCP v2 & v3.
Welcome to the Microsoft Messaging and Mobility User Group: http://www.mmmug.co.uk