The title tells it (almost) all.
I mean to write an answer to
but I get the sign
"protected by Community♦ Sep 21 '12 at 5:39
Thank you for your interest in this question. Because it has attracted low-quality or spam answers that had to be removed, posting an answer now requires 10 reputation on this site. "
According to the sign, I should be able to post an answer. What is the issue?