diff --git a/ChangeLog b/ChangeLog
index 4b04058ec6..5f78f0a43d 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Thu Dec  4 01:37:47 2008  Tadayoshi Funaba  <tadf@dotrb.org>
+
+	* complex.c (nurat_{to_s,inspect}): provides better representation
+	  for in-finite imag part.
+
 Thu Dec  4 01:22:41 2008  Tadayoshi Funaba  <tadf@dotrb.org>
 
 	* complex.c (f_signbit): NaN may be signed value.
diff --git a/complex.c b/complex.c
index 4230af22d6..70eba23ec7 100644
--- a/complex.c
+++ b/complex.c
@@ -922,6 +922,8 @@ nucomp_to_s(VALUE self)
     rb_str_cat2(s, !impos ? "-" : "+");
 
     rb_str_concat(s, f_to_s(f_abs(dat->imag)));
+    if (!rb_isdigit(RSTRING_PTR(s)[RSTRING_LEN(s) - 1]))
+	rb_str_cat2(s, "*");
     rb_str_cat2(s, "i");
 
     return s;
@@ -930,18 +932,11 @@ nucomp_to_s(VALUE self)
 static VALUE
 nucomp_inspect(VALUE self)
 {
-    VALUE s, impos;
-
-    get_dat1(self);
-
-    impos = f_tpositive_p(dat->imag);
+    VALUE s;
 
     s = rb_str_new2("(");
-    rb_str_concat(s, f_inspect(dat->real));
-    rb_str_cat2(s, !impos ? "-" : "+");
-
-    rb_str_concat(s, f_inspect(f_abs(dat->imag)));
-    rb_str_cat2(s, "i)");
+    rb_str_concat(s, nucomp_to_s(self));
+    rb_str_cat2(s, ")");
 
     return s;
 }
diff --git a/test/ruby/test_complex.rb b/test/ruby/test_complex.rb
index 2a193eb155..5d4916e1d0 100644
--- a/test/ruby/test_complex.rb
+++ b/test/ruby/test_complex.rb
@@ -564,6 +564,16 @@ class Complex_Test < Test::Unit::TestCase
       assert_equal('1-2/3i', Complex(1,Rational(-2,3)).to_s)
       assert_equal('-1-2/3i', Complex(-1,Rational(-2,3)).to_s)
     end
+
+    nan = 0.0 / 0
+    inf = 1.0 / 0
+    if nan.nan?
+      assert_equal('NaN+NaN*i', Complex(nan,nan).to_s)
+    end
+    if inf.infinite?
+      assert_equal('Infinity+Infinity*i', Complex(inf,inf).to_s)
+      assert_equal('Infinity-Infinity*i', Complex(inf,-inf).to_s)
+    end
   end
 
   def test_inspect