encrypt and decrypt functions

The only other thing that I could find that might shed some light on why the decrypt function might fail is this:
http://www.adobe.com/support/coldfusion/releasenotes/mx/knownissues_mx_j2ee_p2.html

One known issue was this:
The Encrypt and Decrypt functions do not work with double-byte character sets. If you pass a string containing double-byte characters to the Encrypt function, and later pass the encrypted value to the Decrypt function, the string is not properly decrypted.

But, that list of known issues is dated December 2002, and I imagine that this issue is probably fixed by now.

So, I've found a comment that might shed some light on what might cause the decrypt function not to work. There's a comment at the bottom of this page that seems to suggest that a policy file might need to be updated: http://livedocs.adobe.com/coldfusion/8/htmldocs/help.html?content=functions_e-g_01.html
Does anyone understand this issue well, and if so, can you please explain it?