Is there any coding standard published by microsoft for vba applications?
That's the great thing about standards, there's so many to choose from.
You may be interested in:
Access MVP, Tony Toew's naming conventions: http://www.granite.ab.ca/access/tablefieldnaming.htm
General: Commonly used naming conventions: http://mvps.org/access/general/gen0012.htm
The Leszynski/Reddick Guidelines: http://www.webtracks.biz/web_webtracks/access/LNC.pdf
Just a quicky, but here are a few (free) tools that might help you out: http://delicious.com/Oorang/addin.
If you want to spend some money, IMHO Aivosto's Project Analyzer with the VBA plug is about as quality as you can get for VBA. It can enforce naming standards, catch coding mistakes (google "static code analysis"), provide complexity metrics and much, much more. There is a free version that can handle up to 10 modules, if you are doing something bigger (say a production Access Database) you may have to spring for the full version and then you are into some money. At any rate the site is here:www.aivosto.com