setDate(day+1) returns wrong days
<p>Why does this:</p>

<pre><code>startDate.setDate(startDate + 1);
</code></pre>

<p>Generates this strange order (broken at the beginning of the next month):</p>

<pre><code>7, 27, 28, 30, 30, **1, 4, 3, 4, 4,** 6, 7, 10, 9, 10, 10, 12,
</code></pre>

<p><strong>Update (more code):</strong></p>

<pre><code>renderWeekFromMonday : function(date) {
        var dayContainer = $('#day');

        // clear div
        dayContainer.empty();

        // Render days
        for (var i = 0; i &lt;= 7; i++) {

            // Get mondday day (1-31)
            var day = date.getDate();

            // Today
            var t = new Date();

            // Create dayobject for usage inside for loop
            var d = new Date(date);

            // Render 7 days (1 week)
            for (var i = 0; i &lt; 7; i++) {

                // New day (+1)
                d.setDate(day + i)
                console.info(d.getDate());

                // Create html
                var span = $("&lt;span&gt;").addClass("calElement").attr("time", d.getTime())
                var w = 25;
                span.html("&lt;span class=dayNumber&gt;" + d.getDate() + "&lt;/span&gt;&lt;br&gt;" + this.dayNames[d.getDay()]).css("width",w);
                //span.html("&lt;span class=dayNumber&gt;" + d.getDate() + "&lt;/span&gt;");

                // Append day
                dayContainer.append(span);
            }
        }
    },
</code></pre>
