diff --git a/cameo/fped2stl.pl b/cameo/fped2stl.pl
index 63120ba..df9afc5 100755
--- a/cameo/fped2stl.pl
+++ b/cameo/fped2stl.pl
@@ -60,9 +60,9 @@ print STDERR "$name $z ...\n";
 
 
 while ($ARGV[0] =~ /^-/) {
-	if ($ARGV[0] == "-x") {
+	if ($ARGV[0] eq "-x") {
 		$flip_x = 1;
-	} elsif ($ARGV[0] == "-y") {
+	} elsif ($ARGV[0] eq "-y") {
 		$flip_y = 1;
 	} elsif ($ARGV[0] =~ /^-[^0-9]/) {
 		last;