Link taxonomies

Hi guys,

I have two custom taxonomies in wordpress which are associated to a custom post

one is called section the other called category

I also have a custom posted called product,

so product has two taxonomies ie section and category

I am now in the process of building a super menu which works as follows

It lists all the categories by section

I am guessing I need to query the db directly to get he categories for each section as the product is the only join between them

Can some one point me in the right direction

John