Export Email Messages To PC?

My iPad 2 has an Exchange account with a number of emails (and contacts and calendar) that have been downloaded from the exchange server. I no longer have access to the mail server for this account and need to export the email messages that are still on the iPad to my PC. I do not need to export the calendar or contacts. There is software that will allow me to export Outlook .pst files TO the iPad, but i need to do it the other way round and export the email messages from the iPad to a .pst file on my PC.

There are over 450 folders and sub folders, and over 2,500 individual emails, so forwarding the email messages won't work, and won't preserve the folder structure.