No. The moderators don't have any way to lock a thread. After about 7 replies, you will always see the "No further replies to this post will be accepted." and the "Reply to this Message" button will be missing...
But don't fret, we've been working around this problem for a very long time. In the URL addy for the post, you will see "http://reviews.cnet.com/5208-6130-0" along with some other information. Simply change the 5208 to 5224, leaving everything else the same, then hit the Enter key and you will have a reply window to the post...

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