Fckeditor hangs in Firefox2

Hi

I'm using fckeditor 2.4.2 served by apache2 with php5. These are the php code lines i use to create the editor

$oFCKeditor = new FCKeditor($name) ;
$oFCKeditor->BasePath = '/misc/fckeditor/';
$oFCKeditor->Config['SkinPath'] = 'skins/silver/';
$oFCKeditor->Height = '200';
$oFCKeditor->Width = '400';
$oFCKeditor->ToolbarSet = 'Basic';
$oFCKeditor->Config['ImageBrowserURL'] = $imageBrowserURL;
$oFCKeditor->Config['LinkBrowserURL'] = $linkBrowserURL;
$oFCKeditor->Value = $value;
$oFCKeditor->Create();

But sometimes (i can't find out when) everything goes well but firefox keeps thinking. I mean, all fckeditors in page and all the content is ok, but the page does not load fully.

Any idea of what is happening?

Thank you