Ka-Ping Yee <ping@lfw.org>:
Changes to error messages to increase consistency & clarity.

This (mostly) closes SourceForge patch #101839.
diff --git a/Objects/floatobject.c b/Objects/floatobject.c
index d776147..b58c7fd 100644
--- a/Objects/floatobject.c
+++ b/Objects/floatobject.c
@@ -466,7 +466,7 @@
 	if (iv == 0.0) {
 		if (iw < 0.0) {
 			PyErr_SetString(PyExc_ZeroDivisionError,
-				   "0.0 to a negative power");
+					"0.0 cannot be raised to a negative power");
 			return NULL;
 		}
 		return PyFloat_FromDouble(0.0);
@@ -486,7 +486,7 @@
 		/* Sort out special cases here instead of relying on pow() */
 		if (iv < 0.0) {
 			PyErr_SetString(PyExc_ValueError,
-				   "negative number to a float power");
+					"negative number cannot be raised to a fractional power");
 			return NULL;
 		}
 		errno = 0;