jquery - jquery pointLabel

Question

I am using plot fot plot graphs between two entities,I am struck with representing the point label for the graph I plotted. for the graph I plotted below I need to mention the point value, I tried using with pointLabels: {show: true} but with no luck so far .

code I used :

var t1 = [s1, s2, s3, s4,s5];    
var t2 = [s9, s10, s11, s12,s13];    
var ticks = ['BidsforOpenRequirements', 
             'ShortlistedBidsForOpenRequirements', 
             'ProfessionalsInInterview ',
             'ProfessionalsOnJobs',
             'UnscheduledInterviews'];

var plot1 = $.jqplot('CHART_2', [t1, t2], {        
     seriesDefaults:{
        renderer:$.jqplot.BarRenderer,
        pointLabels: { show: true}
    },
    series: [ { label: 'Contract' }, {label: 'Permanent'} ],        
    legend: {            
        show: true,            
        placement: 'insideGrid'        
    },        
    axes: {            
        xaxis: {                
            renderer: $.jqplot.CategoryAxisRenderer,                
            ticks: ticks 
        },                            
        yaxis: {               
            pad: 1.05,                
            tickOptions: { formatString: '%d' }    
        } 
    }    
});