bibtexVar not correctly returning BIBTEXTYPEKEY for INPROCEEDINGS

[douglasmacharet]

The following code works and prints the correct bibtex key type:

<span class="bibtextypekey"></span>

However, the following operation does not work for INPROCEEDINGS types. The BIBTEXTYPEKEY is returned as undefined:

<div class="bibtexVar" extra="+BIBTEXTYPEKEY+"></div>

What I am trying to do is to use an specific css class for different bibentry types.