diff --git a/ChangeLog b/ChangeLog
index 698807ac50..61326ee40b 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,12 @@
+Mon Jun 10 19:02:19 2002  Nobuyoshi Nakada  <nobu.nokada@softhome.net>
+
+	* numeric.c (fix_lshift): negative shift count means right shift.
+
+	* numeric.c (fix_rshift): return -1 when left side operand is
+	  negative.
+
+	* parse.y (yylex): `0_' should be an error. (ruby-bugs-ja:PR#239)
+
 Sun Jun  9 17:40:41 2002  Takaaki Tateishi <ttate@kt.jaist.ac.jp>
 
 	* ext/dl: change the callback mechanism.
diff --git a/numeric.c b/numeric.c
index accd581133..6722ab0c99 100644
--- a/numeric.c
+++ b/numeric.c
@@ -1422,6 +1422,8 @@ fix_xor(x, y)
     return rb_int2inum(val);
 }
 
+static VALUE fix_rshift _((VALUE, VALUE));
+
 static VALUE
 fix_lshift(x, y)
     VALUE x, y;
@@ -1430,6 +1432,8 @@ fix_lshift(x, y)
 
     val = NUM2LONG(x);
     width = NUM2LONG(y);
+    if (width < 0)
+	return fix_rshift(x, INT2FIX(-width));
     if (width > (sizeof(VALUE)*CHAR_BIT-1)
 	|| ((unsigned long)val)>>(sizeof(VALUE)*CHAR_BIT-1-width) > 0) {
 	return rb_big_lshift(rb_int2big(val), y);
@@ -1448,11 +1452,12 @@ fix_rshift(x, y)
     if (i < 0)
 	return fix_lshift(x, INT2FIX(-i));
     if (i == 0) return x;
+    val = FIX2LONG(x);
     if (i >= sizeof(long)*CHAR_BIT-1) {
-	if (i < 0) return INT2FIX(-1);
+	if (val < 0) return INT2FIX(-1);
 	return INT2FIX(0);
     }
-    val = RSHIFT(FIX2LONG(x), i);
+    val = RSHIFT(val, i);
     return INT2FIX(val);
 }
 
diff --git a/parse.y b/parse.y
index 02b75b4410..f32dafebf1 100644
--- a/parse.y
+++ b/parse.y
@@ -3491,6 +3491,10 @@ yylex()
 			yylval.val = rb_cstr_to_inum(tok(), 8, Qfalse);
 			return tINTEGER;
 		    }
+		    if (nondigit) {
+			pushback(c);
+			goto trailing_uc;
+		    }
 		}
 		if (c > '7' && c <= '9') {
 		    yyerror("Illegal octal digit");