2
           
            
                
     
    
     $module_handler = xoops_gethandler("module"); 
$pd_module = $module_handler->getByDirname("PDdownloads"); 
$comment_handler = xoops_gethandler("comment"); 
 
$criteria = new Criteria("com_modid", $pd_module->getVar('mid')); 
$criteria->setGroupBy("com_uid"); 
$counts_per_user = $comment_handler->getCount($criteria);  
At least for XOOPS 2.2.x, this should work and give you an array of 
uid => number of comments in PD downloads module
    
 
          
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Cusix Software