ntpdate 1:4.2.0a+stable-8.1ubuntu3 (i386 binary) in ubuntu dapper

 NTP, the Network Time Protocol, is used to keep computer clocks accurate
 over the Internet, or by following an accurate hardware receiver which
 interprets GPS, DCF-77, NIST or similar time signals.
 .
 ntpdate is a simple NTP client which allows a system's clock to be set
 to match the time obtained by communicating with one or more servers.
 .
 ntpdate is optional (but recommended) if you're running an NTP server,
 because initially setting the system clock to an almost-correct time
 will help the NTP server synchronize faster.
 .
 The ntpdate client by itself is useful for occasionally setting the time on
 machines that are not on the net full-time, such as laptops.