iOS: fontStyle not supported on iOS

var win1 = Ti.UI.createWindow({

	backgroundColor:'white',

	layout:'vertical'

});

function makeLabel(labelText, labelFont) 

{

    return Titanium.UI.createLabel({

    top: 20,

    text:labelText,

    font:labelFont,

    width:'auto',

    height:'auto'

    });

}

var theTestFont = 'Serif';

win1.add(makeLabel('Font normal normal', { fontFamily:theTestFont, fontWeight:'normal', fontStyle:'normal'}));

win1.add(makeLabel('Font bold normal', { fontFamily:theTestFont, fontWeight:'bold', fontStyle:'normal'}));

win1.add(makeLabel('Font normal italic', { fontFamily:theTestFont, fontWeight:'normal', fontStyle:'italic'}));

win1.add(makeLabel('Font bold italic', { fontFamily:theTestFont, fontWeight:'bold', fontStyle:'italic'}));

win1.open();