accessibilityMeta gives up on nested structs like \section{\emph{Text}}

[frankMilde]

Minimum working example to repoduce bug:

\documentclass[10pt,a4paper]{article}
\usepackage[T1,T2A]{fontenc}
\usepackage[utf8]{inputenc}

\usepackage[tagged]{accessibilityMeta}

\begin{document}
    \section{\emph{Test}}
\end{document}

running pdflatex gives an error

Package accessibilityMeta Warning: You may need to use the babel package or the
 chosen language (english) is not supported by Adobe Acrobat Reader 6. on input
 line 6.

! Undefined control sequence.
<argument> \equal
                  {Section}{Document}
l.8 \section{\emph{Test}}

In a bigger document I got a different message:

[5.6.0.0.3]
! TeX capacity exceeded, sorry [input stack size=5000].
\closeUntilPDFStruct ...bool =0\sectionInDepth {#1
                                                  }{@elemi}\ifnum \@elemi =1...

All works fine if:

1. accessibilityMeta is commented out, or
2. \emph{...} is removed, or
3. {\em ...} is used

My guess is it has something to do with the ifelse package.