Toolbar setting ignored

Hello,

I'm using FCKEditor via PHP integration. Everything works fine otherwise, but it stubbornly keeps ignoring my Toolbar setting.

fckconfig.js has:

FCKConfig.ToolbarSets["Default"] = [
 ...
] ;

FCKConfig.ToolbarSets["Simple"] = [
 ...
] ;

And my PHP code is setting:

$oFCKeditor->ToolbarSet='Simple';

If I look at the page source, it makes it to the iframe code:

<iframe ... src="/static/fwk/fckeditor/editor/fckeditor.html?InstanceName=cms_article_intro&Toolbar=Simple" ...>

But the editor displays the "Default" toolbar nonetheless.

Where exactly am I going off the track?