jsxgraph axis label positioning

HTML

<link rel="stylesheet" href="http://jsxgraph.uni-bayreuth.de/distrib/jsxgraph.css">
<script src="http://jsxgraph.uni-bayreuth.de/distrib/jsxgraphcore.js"></script>
<div id='box' class='jxgbox'></div>

CSS

#box {
    width:500px;
    height:500px;
}

JavaScript

var board = JXG.JSXGraph.initBoard('box', {axis: false, boundingbox: [-10,10,10,-10], grid: true, keepaspectratio: true});


yaxis = board.create('axis', [[0, 0], [0, 1]], {ticks: {label: {offset: [-40, -20]}}});
board.create('point', [1, 1]);