Not able to update Jira user's email where user created during bitbucket issues import

Problem

When a user is created during issues import from bitbucket, the user created in Jira is without email defined although the user account in bitbucket has an email address defined.
Admin is not able to update the user email from the user management page after the user is created.
Due to the email is not defined the user is not able to receive email to reset their password. The Admin will have to reset the password for the user.

This is replicable by importing bitbucket issues to JIRA through Import external projects page.
Then when the Jira admin want to edit the email address for the user from jira user management page, nothing happen when you click save on the edit windows.

Workaround

The user can log into their account to update their email from the profile page. After the email is filled in from profile page, the update email function from the user management page will be working again.