[pmwiki-users] question about BackgroundImages recipe

[SteP]

I guess this is a beginner's question, but the answer isn't really 
apparent to me. To apply a background image to a table I followed the 
BackgroundImages recipe

(:table style='background-image:url
([=http://www.pmwiki.org/pmwiki/uploads/Test/clouds.jpg=]);':)
...
(:tablend:)

and replaced the image url with a custom page variable 
{$myImageUrl}/img.jpg

However, with the above markup the page variable doesn't get expanded. So 
how can I use a variable for the image url? TIA.

--SteP