will be fixed in next build. please see bug 843410.
workaround: change the default handling to "Plugin" in "ClientConsoleModeDefault" parameter in vdc_options table (not engine-config is broken for this one right now so you need to modify the db table directly ATM)
the default is now the same behavior as 3.1. Please verify on sf13.1.
It should open plugin on Win/IE setups. On Win/Firefox or any other unsupperted combination (and also VNC in all cases) it should download console.vv
*** This bug has been marked as a duplicate of bug 843410 ***