Multiple instances of a widget

Hi, I’d appreciate some help with this problem please.

I’d like to be able to add multiple instances of the same widget (with different settings) to my sidebar, but as soon as I add a widget, there is no longer an ‘add’ button next to it in the main list.

Is there a way to add a second (or more) instance of a single widget?

Thanks in advance

(forgot to say – my blog is here)