[horde] Upgrade of Horde from V. 3 to V. 5 failed

[Me]

>You are missing the point. This isn't something that we "decided".
>It's a matter of the case sensitivity of the authentication backend
>(this may be an IMAP server, an LDAP server, a sql server etc...). We
>can't assume that any installation is going to want their usernames
>always lowercased.

Hi Mike,
I understand that the login is dependent on IMAP, LDAP, etc. That is why in many cases it will allow: john or John to log in the same.
The problem is how Horde treats that input.
You said: "We can't assume that any installation is going to want their usernames always lowercased."
If you assume if it is case sensitive or if you assume it is not case sensitive, ether way you are assuming. Why not eliminate the guessing game and ask a question during horde install?
This is not something that just happened to me. If you google the error message: "rampage_users_user_name"  you get 284 forum topics/ posts with the same problem.