Does eM Client support backup (similar to the one in Outlook)?

NULL

I haven’t use Outlook in a long time, but currently eM does not have a bulit-in export feature (or back-up). Back-up has to be done manually (or batch program) of the eM database directory.

C:\Users%Current User%\AppData\Roaming\eM Client (Vista/Win7)
C:\Documents and Settings%Current User%\Application Data\eM Client (XP)

We also plan to implement full backup feature to one of the next versions/updates (probably to next major version 4.0).