I guess I've read most of the SO questions and CKEditor documentation about this, but it does not work for me.

It should be plain and simple, in my CKEditor config.js, I have this :

CKEDITOR.editorConfig = function(config) {

    config.allowedContent = true;

};

But the html is still filtered and this piece of code is being stripped :

<p>

<a href=/site/public/press.pdf><span class=icon-presseFile></span></a>

<a href=/site/public/pics.zip><span class=icon-pressePics></span></a>

</p>

into this :

<p>&nbsp;</p>

The <span> elements are font icons.

Any help would be greatly appreciated.

EDIT
It works if I add some text in the <span> elements (but I don't want tohave to do that)