First of all if you sent 400 messages on one account, you probably won't get shit for leads.
Reason being, those messages will most likely end up in their spam folder, people still get them, BUT myspace is quick on blocking links. When you blast out 400 of the same link, it's probably going to get blocked. The majority of those links you sent out wont even work by the time people click them.
You need to have multiple myspace profiles, and send out maybe 50 messages per account.
That's my experience anyway. I use to use myspace, I'd send out 400 messages on an account and get like 5 leads, then I noticed my myspace messages of people saying "link doesn't work?" so I'd check the link and sure enough Myspace blocked it.
Maybe you already know that, but if not just letting you know.