Replace "Change user name suffix?" with "Change mailbox name suffix?"

On Change Domain name page (virtual-server/rename_form.cgi) you can find ambiguous option Change user name suffix?, which some users believed it's about website username whereas that setting considers only mail boxes. You can see that by reading help text:

By default, existing mailbox users in the domain are not renamed so that their IMAP logins sitll work. You can force a change by setting the Change mailbox name suffix? to Automatically chosen though. This field can also be used to change the suffix to anything you want, even if the domain name is not changed.

No all users spend their time reading help texts, so having precise setting and option names on UI would be nice. Please correct "Change user name suffix?" as "Change mailbox name suffix?"

Thanks!