Whenever you have to explain to a new BlackBerry developer how code signing works you are always sure to get some interesting questions. RIM has been trying their best to make the process a little more transparent and finally made it free but it is still far from simple. RIM gives Microsoft a run for its money when it comes to cryptic error messages and as one commenter points out even something as simple as having a comma in your company code signing name can cause worlds of painful debugging.
Thankfully we now have a pretty solid roundup of resources explaining code signing on the BlackBerry PlayBook (focused on Flash) by an Adobe Developer Evangelist of all people. I really wish RIM simply could make this a zero click process but they are hopefully working on that. Until then check out this great roundup of links and definitions by Renaun Erickson. Let me know if you find any other good resources!