I am not sure what XSS testing you have done with the library but I did find a few XSS attacks that make it partially through the check.
If you would like specific examples you can check out the XSS cheat sheet.
|2007-07-31 18:02:42 - In reply to message 1 from Stephen Lawrence|
What are these attacks? Please send me more details at cristian.navalici [at] gmail to improve the strength of this class.