Quarantine on entry in Dictionary that doesn't exist

I am getting emails quarantined due to a supposed entry in our dictionary that is not in the dictionary.  According to the AS log, the dictionary entry is:

((^|(?<=\d)(?:([ \t])\g{-1}*|([.,]))|[[({:;'' \t>.,])((?!000|666|9\d{2})\d{3}(-|\.|(?:([ \t])?\g{-1}*))(?!00)\d{2}\g{-2}(?!0000)\d{4})($|(?:([ \t])\g{-1}*|([.,]))(?=\d)|[])}:;'' \t<.,]))

I am not good at regex, I've spend an hour at least trying to decypher this.  I most certainly do not have ANY regex entries in the dictionary.  Is there some way I can determine what this regex entry stands for and why I am getting occasional quarantines due to this entry?