diff -r 3f952c6973f7 liboctave/lo-specfun.cc
--- a/liboctave/lo-specfun.cc	Sat Nov 20 09:39:46 2010 -0500
+++ b/liboctave/lo-specfun.cc	Sat Nov 20 22:27:21 2010 +0100
@@ -281,9 +281,6 @@
 double
 xgamma (double x)
 {
-#if defined (HAVE_TGAMMA)
-  return tgamma (x);
-#else
   double result;
 
   if (xisnan (x))
@@ -291,10 +288,12 @@
   else if ((x <= 0 && D_NINT (x) == x) || xisinf (x))
     result = octave_Inf;
   else
+#if defined (HAVE_TGAMMA)
+  return tgamma (x);
+#else
     F77_XFCN (xdgamma, XDGAMMA, (x, result));
-
+#endif
   return result;
-#endif
 }
 
 double
diff -r 3f952c6973f7 src/mappers.cc
--- a/src/mappers.cc	Sat Nov 20 09:39:46 2010 -0500
+++ b/src/mappers.cc	Sat Nov 20 22:27:21 2010 +0100
@@ -918,7 +918,7 @@
 
 %!test
 %! x = [-1, 0, 1, Inf];
-%! v = [NaN, Inf, 1, Inf];
+%! v = [Inf, Inf, 1, Inf];
 %! assert (gamma(x), v);
 %! assert (gamma(single (x)), single (v));