QUOTE
WinZapper is a tool that lets you erase event records selectively from the Security Log in Windows NT 4.0 and Windows 2000. As far as I know there is no other tool capable of doing this.
» OS: Windows NT 4.0 / 2000
» Version: 1.1
» File Size: 29 kb
» First release: 2000.09.05
while clearlogs:
QUOTE
ClearLogs clears the event log (Security, System or Application) that you specify. You run it from the Command Prompt, and it can also clear logs on a remote computer.
» OS: Windows NT 4.0 / 2000 / XP
» Version: 1.0
» File Size: 28 kb
» First release: 2002.02.10
So clearlogs is newer and also for XP

I'll stay by clearlogs