I'm afraid it looks like you might be in a bit of a pickle.
I've noticed that the old article (below) that lists all of the supported OPAL compliant self-encrypting drives has been removed for some reason.
http://www.symantec.com/docs/TECH165854
IIRC, this article only ever listed Hitachi self-encrypting drives as supported anyway (no Samsung drive support). This is supported by the really old Symantec response below:
https://www-secure.symantec.com/connect/forums/see-82-opal-drive-slowness#comment-6162431
The only results coming back when searching for OPAL in the SEE KB are feature requests. All this seems to suggest bad news for your SSD I'm afraid.