Here is a great post on SPC and MSL codes.
Be advised, its a little dated... but the info on the concept is great!
And here's another... Clicky
Then there's THIS
...end of subject

Hi, i bought this Samsung SPH - i330 (Sprint) more than a year ago. There was no service in my area so it just served as a nice paperweight. Recently, CDMA has blown up & the offers are incredible. I tried to get my i330 activated but the tech says its unlocked but he needs the 'SPC' code. I have no idea what that is or if i got any info with the package that'd help me with that. Most of the SW CDs i got are now moisture damaged. Is there any way to get that info from the phone ?
I'm in Jamaica & i dont care much for browser capabilities & such. I just want to be able to take advantage of the offers.

Thanks