I've tried the obvious, a
.po4a.conf file like this:
[po4a_langs] it [po4a_paths] l10n/$master/master.pot $lang:l10n/$master/$lang.po [type: latex] slides.en.tex it:slides.it.tex
But when I run
po4a .po4a.conf, I get a complaint that "frame" is an unknown environment:
slides.en.tex:80: (po4a::tex) unknown environment: 'frame'
The trivial work-around is to treat the LaTeX/Beamer document as a plain text file, but that means that every single line of the document gets pushed to the translation file (in blocks of paragraphs).