php pchart显示中文的有关问题

php pchart显示中文的问题
 $MyData = new pData();   
 $MyData->addPoints(array(25,10,25,10,25,10,25,10,25,10,25,10),"Temperature"); 
 $MyData->addPoints(array(2,4,6,4,5,3,6,4,5,8,6,1),"Pressure"); 
 $MyData->setSerieDrawable("Pressure",FALSE); 
 $MyData->setAxisName(0,"订单总金额"); 
 $MyData->addPoints(iconv_arr(array("一月","二月","三月","四月","五月","六月","七月","八月","九月","十月","十一月","十二月")),"Labels"); 
 $MyData->setSerieDescription("Labels","Months"); 
 $MyData->setAbscissa("Labels"); 

在PHP里使用了pchart，但是标签不显示中文，或显示中文乱码，怎么解决？