I did not identify this problem the first few times it happened, but today I have more evidence.
It seems that sometimes the forum accepts a post, sends out email about it to thread subscribers, and somehow deletes the post without the intevention of the poster.
I've seen this happen a few times, but just thought the post was deleted by the poster [for some reason].
The poster complains in the next post about how his previous post disappeared: http://forums.adobe.com/message/4137889#4137889
I've seen this happen on a few occasions in more than one forum, but I assumed the deletion was deliberate.
Can someone (John?) tell us why the system thinks that post was removed?