First of all, you have to stop spamming your own thread, use the "insert quote" to reply to as many comments as possible all in one comment, posting comments after the other without allowing comments from other users in-between is spam, and could get your account banned.

Secondly, to learn how to sign a message, check this thread https://bitcointalk.org/index.php?topic=990345.0, for the code you posted above can't be verified, I tried but it failed, which means you are doing it wrongly.