[kronolith] Somewhat OT: Upgrade help

[tickticker]

Hello,

Posting this here because the core of my issue is Kronolith.

I have lurked here for about a year or so, and have had 
Horde/imp/kronolith/passwd/forwards/turba running for about 10 months or so fairly stable using release version of all.  works great, love it.  We have invested a bit of energy into customization (mostly look and feel) and the 
mucky mucks just said that they want shared calendars.  If it was just a kronolith issue, no problem.  It's not though, I'm assuming I have to upgrade EveryThing to the RELENG version to get the latest greatest Kronolith going.

Here's the issue, it IS stable, and we have averaged over 50k hits a day since July.  I do have a dev box that I can play with to some extent but I want to roll this out with minimum fuss as the 1800 users are complete and utter end 
users (real estate agents) and as quickly as possible (they change their mind faster than the interest rate).  If I swapped the Inbox and Calendar icons in Imp I would hear from hundreds of them.  Yes they are that bad.

So the question is: Will I need to update EVERYTHING to RELENG to get shared calendars going?  Does anyone have any experience going from the folowing to RELENG?  Going from Imp 2.x was a big change, are there any changes like that out there that will force me to hire my look and feel guy again?

Horde:2.2.1
Imp: 3.2
Kronolith 1.1
passwd 2.2
forwards 2.2
turba 1.1
apache 1.3.27
PHP:4.2.3
MySQL 3.23.58 running backends for Kronolith and Horde
Postfix for mta
Courier-imap
On Redhat 7.3

This upgrade may not be a bad thing though, as IE seems to have password cache problems with our system (requiring logout or password change or reinstall of IE), although the other 12 browsers we tested (including PDA devices) seem to work quite well.  

Thanks in advance,

Anthony
Email Administrator
www.mywestusa.com