DataMapper And Tables Separated By Underscores?

[eluser]Vheissu[/eluser]
Obviously this is a WanWizard question but if anyone else knows the answer your help would be gratefully appreciated.

Basically I have a table called 'products' and then a table called 'product_categories' a product can have many categories, so usually with DataMapper you would create a join table right? So following convention the join table would be called "products_product_categories", would this work or is there something else I need to do?

In the join table, do my field names need to be named differently and do I need to add any parameters to my models?