What's Punjabi?

Punjabi/pa is Gurmukhi Script,

and Western Punjabi/pnb is written in Arabic Script called Shahmukhi.

So Punjabi with default 'pa' goes for Gurmukhi Script, if someone want to translated with Punjabi Western or Shahmukhi script, need to use pa@arb or pnb.

for more references, Please check Mozilla bug: https://bugzilla.mozilla.org/show_bug.cgi?id=380287

Thanks

So pa == pan, or do I stil not get it?

yes, correct pa=pan

Thanks for clearing this up. I'm updating documentation in MediaWiki so this question can be avoided next time :).