Do you mean KDD cup dataset or Keystroke Dynamics Database.

Please don't use acronyms that have more than one meaning.

Further if you already have the database in some form you can easily convert them to CSV/SRFF format.

in case you need to convert into ARFF, you can use this link. I found it in google, and I use many times to convert the data into ARFF format.

http://ikuz.eu/csv2arff/

Here is a full list of different data sets for data mining and knowledge discovery.

http://archive.ics.uci.edu/ml/datasets.html

please, could you send me a copy of KDDCup99 10% percent .arff, if you got it.