Yes, that is an Admin Forum post. Here are the details in brief.
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Hereafter, only reputed members - with a total Thanks + Agree + Useful + Great > 50 - will be able to send Chat & Pvt Messages. Other members will only be able to Reply to pvt messages. They will not be able to initiate pvt. messages or chat request. This will act as a further deterrent to trolls and spammers.