Logo update not reflected on site

Hi

I have changed the logo in the theme using the option Fortuna Option>Header>Upload Logo

There I can see that the logo is correctly uploaded, visible and I clicked the “Save option” button. But on the website, the logo is still missing and when I see the image that is linked and used on the website it’s located here: ../wp-content/themes/fortuna/images/no_img.jpg

So it seems to me that athough the options are correctly saved using the theme option interface, the actual parameters are not reflected on the website.
Can you help us with this?

You can see the maquette of the site here: http://85.236.152.192/~jyb/

thanks

Stéphane