diff --git a/CHANGES b/CHANGES
index 04ed31a..2f3ccab 100644
--- a/CHANGES
+++ b/CHANGES
@@ -4,6 +4,7 @@ CHANGES - 2007-09-15
 CHANGES IN Mini-XML 2.4
 
 	- Added mxmlElementDeleteAttr() function (STR #59)
+	- mxmlElementSetAttrf() did not work (STR #57)
 	- mxmlLoad*() incorrectly treated declarations as parent
 	  elements (STR #56)
 	- mxmlLoad*() incorrectly allowed attributes without values
diff --git a/doc/relnotes.html b/doc/relnotes.html
index 680b09d..905d3e6 100644
--- a/doc/relnotes.html
+++ b/doc/relnotes.html
@@ -11,6 +11,8 @@ hspace="10" width="100" height="100" alt="B"></a>Release Notes</h1>
 
 	<li>Added mxmlElementDeleteAttr() function (STR #59)</li>
 
+	<li>mxmlElementSetAttrf() did not work (STR #57)</li>
+
 	<li>mxmlLoad*() incorrectly treated declarations as parent
 	elements (STR #56)</li>
 
diff --git a/mxml-attr.c b/mxml-attr.c
index 5daf6f4..ddba874 100644
--- a/mxml-attr.c
+++ b/mxml-attr.c
@@ -239,7 +239,7 @@ mxmlElementSetAttrf(mxml_node_t *node,	/* I - Element node */
   value = _mxml_vstrdupf(format, ap);
   va_end(ap);
 
-  if (value)
+  if (!value)
     mxml_error("Unable to allocate memory for attribute '%s' in element %s!",
                name, node->value.element.name);
   else if (mxml_set_attr(node, name, value))