Only the user? Sure, with the Lazy Admin Tool. LAT is written for 6.x, but runs on 7 as well. You will still see some errors, but the author knows about these and will address if pretty soon. In the meantime, you can create some symlinks that will address most of the errors with these line:
ln -s /home/e-smith/db/accounts /home/e-smith/accounts
ln -s /home/e-smith/db/configuration /home/e-smith/configuration
ln -s /home/e-smith/db/domains /home/e-smith/domains
ln -s /home/e-smith/db/hosts /home/e-smith/hosts
ln -s /home/e-smith/db/networks /home/e-smith/networks
Find it here
http://mirror.contribs.org/smeserver/contribs//mblotwijk/Contribs/NB: as of this writing I believe it has some trouble with domain migration, but you only want the users... right? Should work fine.