Svg clip-path within rectangle does not work

I have a simple graph with x and y axes. I don't want the drawing area I draw within to overlap the axes.

I'm using d3 to create my chart but the clip-path does not work:

http://jsfiddle.net/EqLBJ/

var margin = {top: 19.5, right: 19.5, bottom: 19.5, left: 39.5},
    width = 960 - margin.right,
    height = 500 - margin.top - margin.bottom;

var xScale = d3.scale.linear().
    domain([xMin, xMax]). // your data minimum and maximum
    range([0, width]); // the pixels to map to, e.g., the width of the diagram.

var yScale = d3.scale.linear().
    domain([yMax, yMin]). 
    range([0, height]); 

var xAxis = d3.svg.axis().orient("bottom").scale(xScale).ticks(10, d3.format(",d")),
    yAxis = d3.svg.axis().orient("left").scale(yScale);


var chart = d3.select("#chart").append("svg")
    .attr("class", "chart")
    .attr("width", width + margin.left + margin.right)
    .attr("height", height + margin.top + margin.bottom)
    .attr("pointer-events", "all")
    .append("g")
    .attr("transform", "translate(" + margin.left + "," + margin.top + ")")
    .call(d3.behavior.zoom().scaleExtent([0.2, 5]).on("zoom", redraw));


var rect = chart.append('svg:rect')
    .attr('width', width)
    .attr('height', height)
    .attr('fill', 'white');


var line = d3.svg.line()
        .interpolate("basis")
        .x(function(d, i) { return xScale(d.time); })
        .y(function(d) { return yScale(d.value); });

var clip = chart.append("svg:clipPath")
    .attr("id", "clip");

clip.append("svg:rect")
    .attr("id", "clip-rect")
    .attr("width", width)
    .attr("height", height);
    // .attr("fill", "white");

var path = chart.append("svg:path")
    .attr("clip-path", "url(#clip-rect)")
    .data([data])
    .attr("class", "line")
    .attr("fill", "none")
    .attr("stroke", "maroon")
    .attr("stroke-width", 2)
    .attr("d", line);

// x-axis label
chart.append("text")
    .attr("class", "x label")
    .a