Number_to_currency - not accepting all currencies?

Hi,
I am trying to use the following code to have the browser display the
New Israel Shekel, but it is not working
<%= number_to_currency(product.price, :unit => "₪") %>
I also tried
<%= number_to_currency(product.price, :unit => "&nis;") %>
<%= number_to_currency(product.price, :unit => "&shekel;") %>

Does anyone know how I can display the new Israel shekel? It shouls
look like this: ₪

Also, does anyone know of a list of codes you can use to display
different country currency symbols?

Thank you

A google search for 'html entity new isreali shekel' rapidly led me to
suggest &#8362; You could try that.

Colin

That worked, thanks for the help with this