migrating uddeim from J1.5 to J1.7

I am trying to move my site from J1.5 to J1.7 with v2.5 uddeim in both . But unable to restore messages in cb's users' inbox tab. Here's what I did. Let me know if I missed something or if there's a better way.

After installing uddeim in J1.7, I truncated jos_uddeim table.
I exported that table from J1.5 and imported (insert) into J1.7 successfully.
Same for jos_uddeim_emn.

I have unpublished uddeim menu with published menu item linking to uddeim component.

Basically it should work the way you have described above. The problem you might have is that the user IDs in your new Joomla setup are different from the IDs in your old setup.