--- versions/html3_1.pl	Tue Mar 30 20:29:04 1999
+++ versions/html3_1.pl.new	Tue Jul 18 09:27:13 2000
@@ -1731,7 +1731,7 @@
 		    ($this, $_) = &$ctmp($_);
 		    $this = &parse_math_toks($mode,$style,$face,$slevel,1,$this);
 		    @open_tags = @save_open_tags;
-		    undef ($color_env, $inside_math, @save_open_tags);
+		    undef $color_env; undef $inside_math; undef @save_open_tags;
 		};
 	    } elsif ($cmd eq 'left') {
 		#expandable delimiter: make an image
