Charset problem between php ws and app

Hi everyone

I have this App, that querys data from a php ws and a mysql db. Right now I'm having problems with special characters like ñ or accents áíó, etc.

I'm having trouble passing data to ws and back to the app because of this special chars.

DB, php and calls to WS uses charset utf-8 but still some chars shows like Canc%C3%BAn

My code in php is this

$query = "call consultaDetallePropiedad('$idprop');";
        $posts = runProcedureReturnArray( $query );
 
        /* output in necessary format */
        header( 'Content-Type: text/html; charset=utf-8' ); 
        header('Content-type: application/json');
        echo json_encode(array('posts'=>$posts));
 
 
        /* disconnect from the db */
        @mysql_close($link);

var data = 'hash=' + SecureProperties.getString("hash");
        data+= '&do=2&';
        data+= 'idprop=' + propdata.idprop + '&';
        data+= 'desccorta=' + propdata.desccorta + '&';
        data+= 'desclarga=' + propdata.desclarga + '&';
        data+= 'tipoprop=' +  propdata.tipoprop + '&';
        data+= 'operacion=' + propdata.operacion + '&';
        data+= 'idagente=' + propdata.idusuario + '&';
        data+= 'montosol=' +  propdata.montosol + '&';
        data+= 'periodicidad=1&';
        data+= 'dispositivo=tinrobot';
    var uri = 'http://test.com/ws.php?' + data;
 
    var xhr = Titanium.Network.createHTTPClient();
    xhr.open('GET', uri);
    xhr.setRequestHeader('Content-Type', "application/json; charset=utf-8");
    xhr.send();

The data returned from php is

{"posts":[{"post":{"id":"62","desccorta":"Remato Casa sm 30","desclarga":"Remato Casa 2hab y jardin","tipoprop":"Casa Habitacion","operacion":"Venta","callenumero":"Calle Tres Palos #29","colonia":"Sm 30","codigopostal":"77504","delmunicipio":"Canc%C3%BAn ","mtscuad":"0","terreno":"0","recamaras":"0","banosfull":"0","banoshalf":"0","niveles":"0","lugestac":"0","elevador":"0","aguapotable":"EXISTE","regimenprop":"","drenaje":"EXISTE","electricidad":"'EXISTE'","vialidades":"ASFALTO","telefono":"DISPONIBLE","transpub":"EXISTE","vigilancia":"PUBLICA","viasppales":"","geolat":"21.158413451829233","geolng":"-86.83859875329414","geoalt":"0","anoconstruc":"1900","propietario":"","idagente":"3","fechaalta":"0000-00-00","fechapublic":"1900-01-01","montosol":"850000","periodicidad":"1","dispositivo":"tinrobot","avaluo":"0","ultimocambio":"2014-10-30","usucambio":"128ecf542a35ac5270a87dc740918404"}}]}

What do you would do to resolve this situation, almost indicates charset utf-8

Thanks for your help!