[horde] Issue upgrading horde

[Ico Izquierdo]

Hi,
we have 4 balanced servers using memcached running Groupware Webmail 5.2.12

I've stopped, upgraded to 5.2.16 and started one of then and then we 
have Authentication errors:
>  EMERG: HORDE User xxxxxx at upv.es is not authorized for Mail (Host: 
> qqqqqq.upv.es). [pid 22688 on line 340 of 
> "/usr/share/pear/Horde/Registry.php"]

Maybe I did jump some step like clear cache or similar?
Can servers live together with a common memcached and different versions??

Thanks in advance.

-- 
Ico Izquierdo
Analista-Programador
ASIC - UPV