Depends if the file is small enough to fit into memory, if it is here ya go..

-Waswas 
#!/usr/local/bin/perl
my @fileslurp = ();
my $datefld = "";
my $testdate = "200208";
my $newline = "Not the old date\n";
my $thisfile = "/var/tmp/junk.log";

open (FILE,"$thisfile");
@fileslurp = <FILE>;
close FILE;
($datefld) = split(/ /,@fileslurp[$#fileslurp]);
@fileslurp[$#fileslurp] = $newline if ($datefld eq "$testdate") ;
foreach $x (@fileslurp) {
print $x;
}

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In reply to Re: search and replace last line by waswas-fng
in thread search and replace last line by kevinw

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