Today I have found and fixed a severe security exposure in LISTSERV. For obvious reasons, I shall provide NO information regarding the nature of that problem, and I am explicitly asking you not to discuss it on the network in any way which might help potential hackers find out what it is. I could explain how to zap the affected program files to fix the problem, but this would also expose what the problem is, and then it would just be a race between the maintainers and hackers, which could be especially bad as the holidays are not over for everybody. I thought about it and decided that the wisest thing to do was to "close" 1.6b today, after making the necessary changes to make this a "clean" closure, rather than just stopping in the middle of something. Furthermore, all the updated files will bear today's date, so as to "hide" the fix in the mass of other changes: in case a hacker were to get a copy of the code, it would take him much longer to find out what the problem is, and this gives more time to the maintainers to test and install 1.6b. I suppose that's all I can do about it, apart from apologizing for being the cause of the problem in the first place, making sure to recommend serious testing of 1.6b as there will be no beta 1.6b programme, and wishing you good luck. A description of the changes between 1.6a and 1.6b will follow, and I'll then ship the code to everybody. Eric