...

my $IE;
my $IETimeout = 60;

my $timeAtStart; #new global var
...
sub IENavigate( $ ) {
    my $url = shift;
    my $seconds = 0;
    $timeAtStart = time unless ($timeAtStart);
    print "IENavigate $url\n";
    alarm $IETimeout;
    $IE->navigate($url);
    Win32::OLE->MessageLoop();
     
    print "Finished Blocking\n";
    return;
}

sub IEEvent(){
    my ($Obj,$Event,@Args) = @_;
    if (($IETimeout) && ($timeAtStart) && (time > ($timeAtStart + $IETimeout) )) 

{&IEAlarm(17)};
    print "IEEvent '$Event' @ " . time . qq|\n|;
}

##</code><code>##

IEEvent 'StatusTextChange' @ 1131174480
IEEvent 'CommandStateChange' @ 1131174480
IEEvent 'StatusTextChange' @ 1131174480
IEEvent 'StatusTextChange' @ 1131174480
IEEvent 'CommandStateChange' @ 1131174480
IEEvent 'StatusTextChange' @ 1131174480
...
IEEvent 'CommandStateChange' @ 1131174520
IEEvent 'CommandStateChange' @ 1131174520
IEAlarm 17
IEEvent 'CommandStateChange' @ 1131174521
Finished Blocking

##</code><code>##

Use of uninitialized value in concatenation (.) or string at foo.pl line 37.
...
#which is
==36==    my $seconds = IENavigate( $_ );
==37==    print "took $seconds\n";