Just read about a nice small software problem at Opera. Their latest browser is version 10, but they couldn’t continue to use the version number in the user agent string, because some web sites try to identify the agent version and fail with 2 digit version numbers. Seems to be similar to the famous Y2K problem, but now it is a BVN problem – a browser version number problem.
“…It appears that a considerable amount of browser sniffing scripts are not quite ready for this change to double digits, as they detect only the first digit of the user agent string: in such a scenario, Opera 10 is interpreted as Opera 1. This results in sites mistakenly identifying Opera 10 as an unsupported browser, thereby breaking server, as well as client-side scripts…”
Read more at Dev.Opera.