cannot change size of text in tabs

Hello I have 3 tabs in my application. I want to adjust the size of text because if the text size is more then automatically the scroll comes in picture.

`var tabGroup = Ti.UI.createTabGroup();

var win1 = Ti.UI.createWindow({ title : "Home Page" });

var tab1 = Ti.UI.createTab({ icon : "/images/default.png", title : "Text size 1", font : { fontFamily : 'Helvetica Neue', fontSize : 8

},
window : win1

});

tabGroup.addTab(tab1);

var win2 = Ti.UI.createWindow({ title : "Bookmarks Page" });

var tab2 = Ti.UI.createTab({ title : "Text Size 2", icon : "/images/default.png", font : { fontFamily : 'Helvetica Neue', fontSize : 8

},
window : win2

}); tabGroup.addTab(tab2);

var win3 = Ti.UI.createWindow({ title : "Bookmarks Page" }); var tab3 = Ti.UI.createTab({ title : "Text Size 3", icon : "/images/default.png", font : { fontFamily : 'Helvetica Neue', fontSize : 8

},
window : win3

}); tabGroup.addTab(tab3);

tabGroup.open();`

can anyone help? Thanks in advance