Open Source Document Management System | OpenKM

Hi all out there,
I'm completely stuck with a preview issue occurred after moving to 6.3.x release.

The original situation:

• O.S.: Ubuntu server 12.04 LTS, implemented in a KVM Virtual Machine

• OpenKM 6.2.x

• MySQL as database

• LibreOffice 3.x installed

All things working well, preview it's ok.

Becaus I'm getting out of space in the virtual machine, I decided to move the production environment in the host server, UBUNTU 12.04 LTS. So I've installed openkm 6.3.x, installed LibreOffice from repository, moved the repository folder.
All things seems to be ok: I got my repository recovered, my user recovered, my documents and my folder.
But: the icons showing the kind of document (excel, word, ppt, pdf and so on) are replaced by the classic "broken picture" icon and no one document preview is working but the pdf.
So I controlled the configuration and all the setting are correct.
Furthermore, I've noticed that tomcat don't start the soffice program.

I've googled almost everything but I haven't be able to find a solution or a suggestion.
Someone can help me?

Thank You in advance.

is you LibreOffice path correctly configured ? Do you see some error at catalina.log at starting about sigar or similar ?

Yes. The LibreOffice path is well configured.
I used the green check button and ity says it's all ok.
The PDF preview is working.
No "sigar" entry in catalina.log

- Stop OpenKM
- Be sure there's no soffice process running, otherwise kill it.
- Remove all logs into Tomcat/logs
- Start OpenKM
- Try to preview a document

At this point if doesn't go right, post catalina.log file here