Incompatibility with jquery 1.8

[franky]

If you open a dialog with custom buttons, the buttons will shown empty (without "text"-label)

A simple Test: $('<div>Hallo</div>' ).dialog({

resizable: false, height:140, modal: true, buttons: [{text: 'OK' , value: 'ok' , 'class': 'ui-msgbox-ok' }]

});

It works with jquery 1.7.2 and lower fine but with 1.8.0 the buttons are present but empty.

Greetings Frank

[Scott González]

Duplicate of #8484.