Sri Lanka NIC Parser

/**
 * Creates a Javascript Object with gender and date of birth 
 * - extracted from a given valid Sri Lanka N.I.C. Number
 * isu3ru@gmail.com
 */
function parseNIC(nic) {
    var nicdata = {
        gender: '',
        dob: ''
    };

    var pattern = /[0-9]{9}[V|X]/;
    if (!pattern.test(nic)) {
        nicdata.gender = '';
        nicdata.dob = '';
        return false;
    }
    var mon = {
        "1": ["Jan", 31],
        "2": ["Feb", 29],
        "3": ["Mar", 31],
        "4": ["Apr", 30],
        "5": ["May", 31],
        "6": ["Jun", 30],
        "7": ["Jul", 31],
        "8": ["Aug", 31],
        "9": ["Sep", 30],
        "10": ["Oct", 31],
        "11": ["Nov", 30],
        "12": ["Dec", 31]
    };
    if (nic.length >= 5) {
        year = "19" + nic.substr(0, 2);
        days = parseInt(nic.substr(2, 3));
        if (days > 500) {
            nicdata.gender = "Female";
            days = days - 500;
        } else {
            nicdata.gender = "Male";
        }
        var key;
        for (key in mon) {
            if (days > mon[key][1]) {
                days = days - mon[key][1];
            } else {
                break;
            }
        }
        if (days < 10) {
            days = "0" + days;
        }
        nicdata.dob = mon[key][0] + ", " + days + " " + year;
    }
    return nicdata;
}

No support for new nic with 12 digits. only for the old 10 character NIC.