When using the beamer documentclass, it looks like the third level of nested input is ignored:
\documentclass{beamer}
\input{body}
body.tex:
\begin{document}
\input{file1}
\input{file2}
\end{document}
file2.tex:
\input{file21}
The content of file21.tex is ignored with documentclass beamer, but correctly inserted if I use a documentclass article, for example.
Has anyone seen something like this?