High traffic newsgroups are just now reaching a size that cannot be represented in a signed 32 bit number (the number is a little over 2 billion). The latest version of Newsbin (
Version 5.52) uses a 64 bit value to store and process article numbers. If you are not running Version 5.52, you may have issues with large newsgroups (namely alt.binaries.boneless) on some servers. So far Astraweb is the only one we know of that has actually hit the limit but, the others are soon to come.