Side bar isn't showing on archives page of a wordpress blog?

[snowball77]

Hi there,
If you look at this site here:
http://www.bizgro.com.au/blog


you will see there is a sidebar on the right hand side.

If you click on the recent post link like this one
http://www.bizgro.com.au/blog/archives/1

You will see it disappears?

Can anyone help me figure out why this is happening?  Where in the configuration do you ensure the side bar shows on each page?