diff --git a/util/perl/TLSProxy/Proxy.pm b/util/perl/TLSProxy/Proxy.pm
index 48c55f4822..8436861668 100644
--- a/util/perl/TLSProxy/Proxy.pm
+++ b/util/perl/TLSProxy/Proxy.pm
@@ -290,8 +290,14 @@ sub start
     if ($self->debug) {
         print STDERR "Server command: $execcmd\n";
     }
+    my $sin = undef;
+    my $sout = undef;
+    if ("$^O" eq "MSWin32") {
+        $pid = IPC::Open2::open2($sout, $sin, $execcmd) or die "Failed to $execcmd: $!\n";
+    } else {
+        $pid = IPC::Open3::open3($sin, $sout, undef, $execcmd) or die "Failed to $execcmd: $!\n";
+    }
 
-    $pid = IPC::Open2::open2(my $sout, my $sin, $execcmd) or die "Failed to $execcmd: $!\n";
     $self->{serverpid} = $pid;
 
     # Process the output from s_server until we find the ACCEPT line, which