Yii Ajax

hi guys can you please help me I have an dependent element here and a nested ajax. Well i wanted to load the remaining quantity base on what dosage id was loaded. I think my logic is right but it gives me 500(Internal Server Error).

This is my ajax script:

<script>

&#036;(document).ready(function(){


&#036;.ajax({


    type: 'POST',


    data: {cons_medname: &#036;('#ShisConsultation_cons_medname').val()},


    url: '&lt;?php echo CController::createUrl('onload'); ?&gt;',


       success: function(data){


         &#036;('#ShisConsultation_cons_dosage').append(data);


	&#036;.ajax({


	    type: 'POST',


	    data: {cons_dosage: &#036;('#ShisConsultation_cons_dosage').val()},


	    url: '&lt;?php echo CController::createUrl('quantity'); ?&gt;',


	    success: function(data){


	        &#036;('#remaining').text(data);


	    }


	});


       }


    });


 });

</script>

This is my action controller:

public function actionDosage()

{

&#036;criteria = new CDbCriteria;


&#036;criteria-&gt;condition = 'dtl_med_id='.&#036;_POST['cons_medname'].' AND dtl_qty&#33;=0';


&#036;data=ShisMedDetails::model()-&gt;findAll(&#036;criteria); 


&#036;data=CHtml::listData(&#036;data,'dtl_id','dtl_dosage');


echo CHtml::tag('option',


array('value'=&gt;''),CHtml::encode(&quot;Select Dosage&quot;),true); 


foreach(&#036;data as &#036;value=&gt;&#036;name)


{


echo CHtml::tag('option',


array('value'=&gt;&#036;value),CHtml::encode(&#036;name),true);


}

}

public function actionQuantity()

{

&#036;criteria = new CDbCriteria;


&#036;criteria-&gt;condition = 'dtl_id='.&#036;_POST['ShisConsultation']['cons_dosage'];


&#036;data=ShisMedDetails::model()-&gt;find(&#036;criteria);


echo CHtml::tag('label', array(),CHtml::encode(&#036;data-&gt;dtl_qty),true);

}

in addition if i put a static query in actionQuantity it gives me no error tnx.