Usegroup MassAdd wont work

[chokies]

Hi guys care to help me out ive been struggling to make this thing work.. but seem to have some issue with it

below is my json request

{
"auth":"6bf1b66f5d9a78d79f43bfb024279242",
"method":"usergroup.massAdd",
"id":1,
"params":{
	"usrgrpids":["56"],
	"rights":[
		{"permisssion":3,"id":"43"}
		]
	},
"jsonrpc":"2.0"}

Array
(
    [auth] => 6bf1b66f5d9a78d79f43bfb024279242
    [method] => usergroup.massAdd
    [id] => 1
    [params] => Array
        (
            [usrgrpids] => Array
                (
                    [0] => 56
                )

            [rights] => Array
                (
                    [0] => Array
                        (
                            [permisssion] => 3
                            [id] => 43
                        )

                )

        )

    [jsonrpc] => 2.0
)

im getting this error

Array
(
[code] => -32400
[message] => System error.
[data] => JSON-rpc error generation failed. No such error:
)

[chokies]

We got it working already.. took us lots of hours just to figure out there is something wrong with the example in the manual. Permission is misspelled "permisssion" having 3 s..