Hey, the POD of Win32::EventLog show how you can READ from the Event Viewer, not write to it. Perhaps I read your question incorrectly? In which case I apologize, but you can write to it very easily:
#!/usr/bin/perl -w
use strict;
use Win32::OLE;
my ($app)=Win32::OLE->new("WScript.Shell");
$app->LogEvent(4,"You know it man!");
1;