Our company security office recommends going to a TLS based data driver going from SQL2005 server to IBM AS400 ( so called i-series ) DB2 host. Where to find such TLS based driver ? Your help is greatly appreciated.

Working with IBM is difficult.  If you need anything related to their software, I found it best to just call their support directly.  I tried to install the AS400 drivers for Windows through their website below.  Only to find out that language packs are no longer offered as part of their service packs.  Just have your IBM number handy or they will refuse to work with you.

http://www-03.ibm.com/systems/power/software/i/access/windows.html