Hello.
I know this is addressed but I thought I would share my expirence in this. This is what I am actually doing professionally right now... so I have some expirence in it. My organization does is a leader in doing these sorts of migrations. We are a TransVault partner and have a similiar migation utility we made and sell (globanet migrate).
A lot of this depends on what you want. You can restore (rehydrate) the items back to a users mailbox and then migrate have the items archived in EV. This is one way to do it. Prior to letting EV touch your site.... I would strongly encourage you to disable the EMX message class from being archived in EV. It causes all sorts of problem for any migration.
That said every solution has its shortcomings. We can certianly do migrations that rebuild the message location and folder structure, and we can also rebuild bcc information that was initially captured by EMX into an envelope created for archived messages so that you can have consistancy in discovery and compliance searches.
I think there are a few things you have to consider:
1) Do you want to migrate Journal content from EMX to EV? If yes is this data going to be used for Compliance or Legal discovery?
2) Do you only want to migrate items that are represented as shortcuts in a users mailbox or do you want to migrate all contents that is in the EMX archive for that user?
3) Do you want to convert shortcuts as part of this process?
All of this can be done and there are a lot of options within each of these. I think this gets you off to a start.
There is also the issue of understanding some of the differnces between EMX and EV's archiving methodology. In an EMX enviornment that is Journaled, most times the content is archived by the Journal..and then is retroactively shortcutted in the user mailbox. This leaves one single archive where users have access to the content they were sent.
EV has seperate archives for each user.. and a Journal can be associated with several targets.
The reason this is important is because if you are seeking to migrate the Jouranl and all the users archived content... you end up migrating about double what you presaently have. It gets Single instanced by EV and does not take up double the space (depending on EV config) but it still goes through the migration process.
There is a third party partner product that emulates EMX access functionality in EV>....but I dont know much about it outside of its existance.
I hope this helps. If you would like to talk to someone about this so you can have some help in guaging what direction is best for you... please let me know and I will get someone in contact with you.
I hope this helps.
J