[horde] My administrative account suddently blank

[Tô]

Hi list,

I have a big, big...big problem with Horde.
I simply exported/imported my bookmarks from a test install (CVS) to a 
prod install (last stables modules) of Horde (same web server with two 
diffents mysql databases on a Kolab server) and, suddently...a totally 
blank screen after a successfull connection, in each of theese 
environments !
Nothing in log files, no messages (except after import : something like 
"error, mailbox does not exit").

It clearly has to do with Trean import, but I absolutely don't know how 
to deal with this.
I cleared Trean install and disabled it in "horde/config/registry.php", 
but got always this totally blank screen.
I wonder where are Trean's data stored ?

Other users can connect with no problem at all... just me, the 
administrator !!

Can somebody point me in a right direction ? (it's not critical, but, 
I'd like not to loose all my mails, events, notes and so on...if I have 
to create a new account)

Many thanks in advance,

Christophe