Writing a file with Encryption

Hi,

I am using a Web Dynpro Application to write a text file. However I am able to write the file , but I want the data of the file to be encrypted using any one of the common Encryption Standards. Is there a way to do this in SAP NWDS 04/04s within a Web Dynpro application.

Is there a way out by adding a class or by any other means.

Plz help if this is possible.