[opencms-dev] Upgrade opencms 5.0.1 to 6.x

[miguel]

Dear All,
   I manage a site with opencms 5.0.1/Tomcat 4.1/Oracle 8.1.7, and I 
wanna upgrade opencms to 6.x version. I am looking for documentation 
about it, but I have found nothing. I would like know:
a) Is there any process to upgrade opencms 5.x to 6.x ? , of course the 
information of the data base must go on working.
b) Is there documentation about upgrade opencms 5.x to 6.x ?

Thank you