This security enhancement is new in the Solaris 10 6/06 release.
Advanced Encryption Standard (AES) is a block cipher recommended by the National Institute of Standard and Technology (NIST). When used in counter mode, a counter block is encrypted and the result is XOR with a block of plain text to produce cipher text. The counter mode is useful with block devices because the encryption or decryption of a block does not depend upon the prior encryption or decryption of any other block. The counter mode has been approved by NIST. This feature is only available to kernel consumers.
For more information, see the libpkcs11(3LIB) man page.