changing of ToolbarSets options

How can I change ToolbarSets options in my start page
for example
$oFCKeditor1 = new FCKeditor('content1');
$oFCKeditor1->BasePath = '';
$content1 = $oFCKeditor1->Create();

i need varinte like
$oFCKeditor1->ToolbarSet['Default']['Source']="-";

Is this possible ?
Thanks