diff --git a/ChangeLog b/ChangeLog
index b7ba9ed8f7..c946046158 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -24,6 +24,17 @@ Tue Sep  5 05:49:41 2006  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 	* file.c (path_check_0): check if sticky bit is set on parent
 	  directories for executable path.  fixed: [ruby-dev:29415]
 
+Tue Sep  5 05:03:46 2006  Yukihiro Matsumoto  <matz@ruby-lang.org>
+
+	* numeric.c (fix_plus): addition in Fixnum will never overflow
+	  long.  a patch from Ondrej Bilka <neleai at seznam.cz>.
+	  [ruby-core:08794]
+
+	* numeric.c (fix_minus): ditto.
+
+	* bignum.c (rb_big_pow): eagerly truncate resulting bignum.
+	  [ruby-core:08794]
+
 Mon Sep  4 23:15:34 2006  Yukihiro Matsumoto  <matz@ruby-lang.org>
 
 	* time.c (time_to_s): make it conform to RFC2822 date format.
diff --git a/bignum.c b/bignum.c
index 6a7a83c085..df702e26ca 100644
--- a/bignum.c
+++ b/bignum.c
@@ -1617,8 +1617,10 @@ rb_big_pow(x, y)
 		while (yy % 2 == 0) {
 		    yy /= 2;
 		    x = rb_big_mul(x, x);
+		    if (!BDIGITS(x)[RBIGNUM(x)->len-1]) RBIGNUM(x)->len--;
 		}
 		z = rb_big_mul(z, x);
+		if (!BDIGITS(z)[RBIGNUM(z)->len-1]) RBIGNUM(z)->len--;
 	    }
 	    return bignorm(z);
 	}
diff --git a/numeric.c b/numeric.c
index c5e9893c03..3ae1c283d5 100644
--- a/numeric.c
+++ b/numeric.c
@@ -1982,11 +1982,8 @@ fix_plus(x, y)
 	a = FIX2LONG(x);
 	b = FIX2LONG(y);
 	c = a + b;
-	r = LONG2FIX(c);
+	r = LONG2NUM(c);
 
-	if (FIX2LONG(r) != c) {
-	    r = rb_big_plus(rb_int2big(a), rb_int2big(b));
-	}
 	return r;
     }
     if (TYPE(y) == T_FLOAT) {
@@ -2015,11 +2012,8 @@ fix_minus(x, y)
 	a = FIX2LONG(x);
 	b = FIX2LONG(y);
 	c = a - b;
-	r = LONG2FIX(c);
+	r = LONG2NUM(c);
 
-	if (FIX2LONG(r) != c) {
-	    r = rb_big_minus(rb_int2big(a), rb_int2big(b));
-	}
 	return r;
     }
     if (TYPE(y) == T_FLOAT) {