Thread:Project:Support desk/DynamicPageList within template

I'm using MediaWiki 1.23.2. I want to include a DynamicPageList within a template like so:

And then supply the category when the template is included somewhere else, however when I try to do that, it just prints "Error: You need to include at least one category, or specify a namespace!".

I've checked the source code for the dynamic page list and it seems that doesn't get translated to the actual parameter properly. Is there a way to change that?