spammers keep appearing in my @replies

My twitter page is locked. When I check my @replies, I keep seeing people I don't know, who don't follow me and I don't follow them, repeating an @reply that one of my friends sent me a week ago. They don't Retweet it properly, they just copy the tweet from my friend (with my name included) and then add a bunch of unrelated stuff at the end.
These are all brand new accounts doing this, mostly porn looking profiles. Girls in lingerie posting links to webcams, etc.
I am sick of seeing all these strangers appearing to be replying to me, when they don't even follow me.

Here is one example but there are many others, and they all repeat the same tweet about a Halloween trip to Illinois.:
http://twitter.com/JusticeCopk/status...
(I am eeklips)(My friend tweeted the first sentence to me, but the rest is copied from other people)
They seem to be copying random tweets related to Halloween, and none are properly RT with the original author's name..
I wouldn't even care if they just copied the tweet WITHOUT my name in it, because then it wouldn't show up in my @replies.
What can I do to stop this cycle, other than just blocking the people?