if I understand the question right.. there may be an option in the editor?..
Link on Ckeditor docs site
Setting it to true forces the editor to discard all formatting when pasting text. It will also disable the Paste from Word operation.
FCKConfig.ForcePasteAsPlainText = true ;
By default the option is set to false.
Using the answer from Case42 (Thanks Case!), paste the following in the config.js file in the wysiwyg folder:
CKEDITOR.editorConfig = function( config )
config.forcePasteAsPlainText = 'true';
Works here with Q2A 1.4.1.