It is an old form once used in France. It is always mentioned in historical grammar books. The examples often given are taken from classic authors' works. Here is one (in François le Champi, by George Sand, Mid-19th century):
http://fr.wikisource.org/wiki/Fran%C3%A7ois_le_Champi/Chapitre_4
(6th dash, counting from the bottom of the page: "Vous êtes toujours après laver et peigner Jeannie").

Some old folks might still use it in the country today, but I don't remember ever hearing it (everybody use "être en train de..." in France today).

+ The expression can be found in many regional glossaries. Here is one published on Internet (Vendée is a western France province).

http://dico.troospeanet.fr/show.php?id=58

All these words have been heard by the people who added them ("N’hésitez pas à nous proposer des mots nouveaux, POURVU QU'ILS SOIENT ENCORE EN USAGE").

See Jim Leger's blog teaching Cajun French. See the comments sections with posts from both Cajuns and Canadians about their using être après:

http://cajunlanguage.net/2010/07/jsus-toujours-ici-apres-esperer-attendre-et-souhaiter/

Also see Louisiana State University's website on Cajun French: http://appl003.lsu.edu/artsci/frenchweb.nsf/$content/Cajun+French+Glossary?OpenDocument

Guys,

Interesting analysis guys ..

I wish I could help .. but the only dialect that I'm
familiar with with Cudahy-eese.

"Ya dere, hey!"
"Drive on up to Monkey Wards"
"It'll cost you a buck two-fifty."
"How 'bout dem dere Packers, eh?"
"Ya, I seen it too, dere!"

--bn

Ah, Big...takes me back to my yout in the South Side of Milwaukee.

Chuck,

That's funny .. You were able to identify a geographical
location on planet Earth within a few miles, simply
based on a few common colloquialisms!

I'll bet that's possible in SW Louisiana too

--bn

Ya, hey, I lived on South Superior, ya know?

I know this isn't the term he is asking for but après is also a command. Borrowed from the wikibooks (Link #1) on Louisiana French. I helped write the book; so please don't take it as authority.

Va après de l'eau. = Go get some water (now).

Thank you to everyone for helping me understand this!