Bug in Ext Calendar Pro 1.5 beta (with ExtJs4): October 2011 has 32 days

Add this code before your application code.

    
    Extensible.Date.add = function(dt, o) {
        if (!o) {
            return dt;
        }
        var ExtDate = Ext.Date,
            dateAdd = ExtDate.add,
            newDt = ExtDate.clone(dt);

        if (o.years) {
            newDt = dateAdd(newDt, ExtDate.YEAR, o.years);
        }
        if (o.months) {
            newDt = dateAdd(newDt, ExtDate.MONTH, o.months);
        }
        if (o.weeks) {
            o.days = (o.days || 0) + (o.weeks * 7);
        }
        if (o.days) {
            newDt = dateAdd(newDt, ExtDate.DAY, o.days);
        }
        if (o.hours) {
            newDt = dateAdd(newDt, ExtDate.HOUR, o.hours);
        }
        if (o.minutes) {
            newDt = dateAdd(newDt, ExtDate.MINUTE, o.minutes);
        }
        if (o.seconds) {
            newDt = dateAdd(newDt, ExtDate.SECOND, o.seconds);
        }
        if (o.millis) {
            newDt = dateAdd(newDt, ExtDate.MILLI, o.millis);
        }

        return o.clearTime ? ExtDate.clearTime(newDt) : newDt;
    }

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