I posted an answer to this question. In view of further information provided by the OP in response to my answer, my answer is irrelevant to the question that the OP really should have asked. He has accepted @phonon's answer already. I want to delete my answer but want to make sure that this is OK with the powers that be, because my answer has received two upvotes. I remember reading here that deleting upvoted answers is considered to be inappropriate behavior on this site.
I don't think we have a very strict policy on answer deletion, so it's up to you to keep it or not. I don't think that deleting it will serve any great purpose, since another answer has already been accepted and it's quite obvious from the comments that the question has been modified.
$\begingroup$ Thanks for the clarification. I have deleted my an amswer. $\endgroup$ Dec 13, 2011 at 23:06