diff --git a/ChangeLog b/ChangeLog
index 014ea777..31aa9262 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,8 +1,13 @@
+Thu Jul  9 08:43:06 CEST 2009 Daniel Veillard <daniel@veillard.com>
+
+	* tree.c: avoid calling xmlAddID with NULL values
+	* parser.c: add a few xmlInitParser in some entry points
+
 Thu Jun  4 11:17:23 CEST 2009 Daniel Veillard <daniel@veillard.com>
 
 	* c14n.c debugXML.c doc/examples/io2.c parser.c schematron.c
 	  valid.c xmlschemas.c xmlwriter.c xpath.c: use %s to printf string
-	  patch by Christian Persch
+	  patch by Christian Persch, fixes #581612
 
 Thu Jun  4 11:06:07 CEST 2009 Daniel Veillard <daniel@veillard.com>
 
diff --git a/parser.c b/parser.c
index bcaec7fd..6659f2c0 100644
--- a/parser.c
+++ b/parser.c
@@ -13568,6 +13568,8 @@ xmlSAXParseMemoryWithData(xmlSAXHandlerPtr sax, const char *buffer,
     xmlDocPtr ret;
     xmlParserCtxtPtr ctxt;
 
+    xmlInitParser();
+
     ctxt = xmlCreateMemoryParserCtxt(buffer, size);
     if (ctxt == NULL) return(NULL);
     if (sax != NULL) {
@@ -13593,7 +13595,7 @@ xmlSAXParseMemoryWithData(xmlSAXHandlerPtr sax, const char *buffer,
     if (sax != NULL) 
 	ctxt->sax = NULL;
     xmlFreeParserCtxt(ctxt);
-    
+
     return(ret);
 }
 
@@ -13656,14 +13658,16 @@ xmlDocPtr xmlRecoverMemory(const char *buffer, int size) {
  *
  * A better SAX parsing routine.
  * parse an XML in-memory buffer and call the given SAX handler routines.
- * 
+ *
  * Returns 0 in case of success or a error number otherwise
  */
 int xmlSAXUserParseMemory(xmlSAXHandlerPtr sax, void *user_data,
 			  const char *buffer, int size) {
     int ret = 0;
     xmlParserCtxtPtr ctxt;
-    
+
+    xmlInitParser();
+
     ctxt = xmlCreateMemoryParserCtxt(buffer, size);
     if (ctxt == NULL) return -1;
     if (ctxt->sax != (xmlSAXHandlerPtr) &xmlDefaultSAXHandler)
@@ -13673,7 +13677,7 @@ int xmlSAXUserParseMemory(xmlSAXHandlerPtr sax, void *user_data,
 
     if (user_data != NULL)
 	ctxt->userData = user_data;
-    
+
     xmlParseDocument(ctxt);
     
     if (ctxt->wellFormed)
diff --git a/tree.c b/tree.c
index be5c6b96..6d0e95b7 100644
--- a/tree.c
+++ b/tree.c
@@ -1860,7 +1860,8 @@ xmlNewPropInternal(xmlNodePtr node, xmlNsPtr ns,
         }
     }
 
-    if (xmlIsID((node == NULL) ? NULL : node->doc, node, cur) == 1)
+    if ((value != NULL) &&
+        (xmlIsID((node == NULL) ? NULL : node->doc, node, cur) == 1))
         xmlAddID(NULL, node->doc, value, cur);
 
     if ((__xmlRegisterCallbacks) && (xmlRegisterNodeDefaultValue))