web client vsphere 5.1, ESX5.1, linux firefox 31, fedora 19 launch a console: error opening virtual machine VM-XX: a connection to the server could not be stablished

Hi,

I have a vcenter 5.1, installed from a vAPP, when using the web client in a linux machine, fedora 19 with firefox ver31  the message

"error opening virtual machine VM-XX: a connection to the server could not be stablished"   shows up

• vclient installed in a windows machine to open consoles works fine
• I can do ssh to the vsphere server, no problem.
• I am in a LAN, no firewalls in between
• I can do other task in the webclient (clone VM, migrate, etc)

so Just that I can't open consoles.

So I will start asking, anyone use linux and webclient and is able to open consoles?

Any ideas on where to start to debug?

Thanks in advance