There seems to be a bit of misunderstanding (based on what I've read on a few profiles) about the difference between Private Messages and Profile Messages.
Private Messages are akin to emails, except they can only be written, sent and read from within the forum. Private Messages are not visible to other forum members.
Profiles Messages are posts to a member's profile. These can be read by any registered forum member and are subject to the forum rules like any other post.
If you want to send a message to another member that cannot be seen by anyone but the two of you, you want to send a Private Message.
If you want to leave a message for another member that can be read by anyone logged in to the forum, you want to leave a Profile Message.
I hope that helps clarify the difference between the two forms of forum messaging. If you have any questions about how to use features of the forum, please post your question to the Site Operations forum and we'll attempt to provide a satisfactory explanation.
As the rules state, questions regarding moderation or forum policies should be posed via PM. That's Private Message, not Profile Message.