yes, I have experienced it. People don't check the messages - the computer does, so if it looks like you are sending website info or telephone numbers, the computer blocks it.

Another flaw built into their system: someone sent me a message saying he would be interested in buying an item at a lower price, but he did not use the "make an offer" feature (and did not mention a dollar amount). I responded that I might be receptive after the auction ends. That got me a warning that I was trying to make a sale outside Ebay and that my account could be suspended if it happens again. Now I don't respond to that type of inquiry.