diff --git a/ChangeLog b/ChangeLog
index d64a3d2729..88987b109b 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,10 @@
+Mon Mar 31 10:50:48 2003  Yukihiro Matsumoto  <matz@ruby-lang.org>
+
+	* hash.c (env_reject_bang): untaint key string.
+
+	* hash.c (env_delete_m): execute block only if deleting key does
+	  not exist.
+
 Sat Mar 29 17:54:46 2003  Yukihiro Matsumoto  <matz@ruby-lang.org>
 
 	* pack.c (pack_pack): do not call rb_str_buf_cat() with NULL ptr,
diff --git a/hash.c b/hash.c
index 1bb4c93bf6..a2fa1fdcdf 100644
--- a/hash.c
+++ b/hash.c
@@ -1002,8 +1002,10 @@ static VALUE
 env_delete_m(obj, name)
     VALUE obj, name;
 {
-    VALUE val = env_delete(obj, name);
-    if (rb_block_given_p()) rb_yield(name);
+    VALUE val;
+
+    val = env_delete(obj, name);
+    if (NIL_P(val) && rb_block_given_p()) rb_yield(name);
     return val;
 }
 
@@ -1342,6 +1344,7 @@ env_reject_bang()
 	VALUE val = rb_f_getenv(Qnil, *ptr);
 	if (!NIL_P(val)) {
 	    if (RTEST(rb_yield(rb_assoc_new(*ptr, val)))) {
+		FL_UNSET(*ptr, FL_TAINT);
 		env_delete(Qnil, *ptr);
 		del++;
 	    }
diff --git a/lib/benchmark.rb b/lib/benchmark.rb
index 16c4cb611a..b664841fe6 100644
--- a/lib/benchmark.rb
+++ b/lib/benchmark.rb
@@ -450,11 +450,11 @@ module Benchmark
     STDOUT.sync = sync
   end
 
-  def bm(label_width = 0, *labels, &blk)
-    benchmark(" "*label_width + CAPTION, label_width, FMTSTR, *labels, &blk)
+  def bm(label_width = 0, *labels)
+    benchmark(" "*label_width + CAPTION, label_width, FMTSTR, *labels){|*x|yield *x}
   end
 
-  def bmbm(width = 0, &blk)
+  def bmbm(width = 0)
     job = Job.new(width)
     yield(job)
     width = job.width