Hi ingvar_j,
"Question: What do I have to do in order to remote install a later version like RH/Centos 6.4 or 6.5 ?"
Nothing! support is built in.
in any case - you can find RH/CentOS 6.4 at :
http://www.mellanox.com/downloads/Drivers/DUD/DUD-mlnx_en-2.0-3.0.0-rhel6.4.tgz