The change is indeed for integrity (not security) reasons. If you do a GET with the NOLOCK option, LISTSERV is free to continue modifying the list. If you then do a PUT, changes made by LISTSERV will be lost, and noone will be notified. So, when you use NOLOCK, LISTSERV doesn't add the PUT line. When you do NOLOCK *and* HEADER, meaning you will only modify the header, LISTSERV will write the PUT line in 1.8b but this is not the case in the base 1.8a. UBVM is running an advance release of some of the 1.8b changes and in this respect behaves like 1.8b. Eric