diff --git a/build/zoneinfo2lua.pl b/build/zoneinfo2lua.pl
index e4e637292d..c996634444 100755
--- a/build/zoneinfo2lua.pl
+++ b/build/zoneinfo2lua.pl
@@ -39,7 +39,8 @@ while( ! eof ZTAB ) {
 		close ZONE;
 
 		if( $tz ) {
-			$zone =~ s/_/ /g;
+			# Don't replace underscores with spaces: correct names contain underscores.
+			# $zone =~ s/_/ /g;
 			$TZ{$zone} = $tz;
 		}
 	}
diff --git a/build/zoneinfo2ucode.pl b/build/zoneinfo2ucode.pl
index 941255f2f4..c902087008 100755
--- a/build/zoneinfo2ucode.pl
+++ b/build/zoneinfo2ucode.pl
@@ -33,7 +33,8 @@ while( ! eof ZTAB ) {
 		close ZONE;
 
 		if( $tz ) {
-			$zone =~ s/_/ /g;
+			# Don't replace underscores with spaces: correct names contain underscores.
+			# $zone =~ s/_/ /g;
 			$TZ{$zone} = $tz;
 		}
 	}