For all languages except Polish, the sysinfo messages live in a file called sysinfoMessages_????.properties, where ???? is the name of the locale. For Polish messages, the M is not capitalized, and the filename is sysinfomessages_pl.properties. On platforms with case-sensitive file names (like Linux), Derby's message resolution machinery probably doesn't find the Polish translations of sysinfo messages. If this is confirmed, we should fix this problem by renaming sysinfomessages_pl.properties to sysinfoMessages_pl.properties.