I thought it was something like that. I can also envision this happening if a page is created incorrectly; the topic is incorporated into another, or something of the sort.
Is it a template that places the WARNING notice? Can the person placing it also put a note on the talk page: deleted because this was stupid don't put it back/deleted because this has been incorporated into [[Aztec Fishing Gear]]/deleted because this was a WP stub which remained untouched for years, feel free to start again from scratch?
I'm not sure what's causing it. It's not a template or anything. As far as I can tell, it's a default we picked up somewhere. Possibly in the shipping version of MW 1.10 (although I've never heard of it on WP). I think that mentions on Talk Pages might not be a bad idea.
In short Mr. Schroder, please do create the article. Ironically, it was created to open up the space to encourage others to build a quality article there. So I again apologize for the tone of the default message (which I can't seem to find in order to soften).