"Error in property <waypoints>"

I am using google map api v3,

I store coordinates into an array and supply the whole array to the waypoints as below:

var request{
origin:start,
destination:end,
waypoints:arrayOfCoordinates,
}

When I run my code it gives me following error:

Uncaught Error: Error in property <waypoints>: (Invalid value: [object Object],[object Object],[object Object],[object Object],[object Object] (Error in element at position 4: (Unknown property <x>)))
gen_204:-1Resource interpreted as Image but transferred with MIME type text/html.

Any idea?

One of the arguments, the fourth one, is missing.