Index: Include/pyexpat.h
===================================================================
--- Include/pyexpat.h	(revision 51208)
+++ Include/pyexpat.h	(working copy)
@@ -42,6 +42,9 @@
         XML_Parser parser, XML_UnknownEncodingHandler handler,
         void *encodingHandlerData);
     void (*SetUserData)(XML_Parser parser, void *userData);
+    XML_Size (*GetCurrentLineNumber)(XML_Parser parser);
+    XML_Size (*GetCurrentColumnNumber)(XML_Parser parser);
+    XML_Index (*GetCurrentByteIndex)(XML_Parser);
     /* always add new stuff to the end! */
 };
 
Index: Lib/test/test_xml_etree_c.py
===================================================================
--- Lib/test/test_xml_etree_c.py	(revision 51208)
+++ Lib/test/test_xml_etree_c.py	(working copy)
@@ -204,6 +204,17 @@
         "<?xml version='1.0' encoding='%s'?><xml />" % encoding
         )
 
+def check_xml_file_positioning():
+    """
+    >>> xb = ET.XMLTreeBuilder()
+    >>> xb.CurrentLineNumber
+    1
+    >>> xb.CurrentColumnNumber
+    0
+    >>> xb.CurrentByteIndex
+    -1
+    """
+
 def test_main():
     from test import test_xml_etree_c
     test_support.run_doctest(test_xml_etree_c, verbosity=True)
Index: Modules/pyexpat.c
===================================================================
--- Modules/pyexpat.c	(revision 51208)
+++ Modules/pyexpat.c	(working copy)
@@ -2050,6 +2050,9 @@
     capi.SetProcessingInstructionHandler = XML_SetProcessingInstructionHandler;
     capi.SetUnknownEncodingHandler = XML_SetUnknownEncodingHandler;
     capi.SetUserData = XML_SetUserData;
+    capi.GetCurrentLineNumber = XML_GetCurrentLineNumber;
+    capi.GetCurrentColumnNumber = XML_GetCurrentColumnNumber;
+    capi.GetCurrentByteIndex = XML_GetCurrentByteIndex;
     
     /* export as cobject */
     capi_object = PyCObject_FromVoidPtr(&capi, NULL);
Index: Modules/_elementtree.c
===================================================================
--- Modules/_elementtree.c	(revision 51208)
+++ Modules/_elementtree.c	(working copy)
@@ -2574,6 +2574,19 @@
         sprintf(buffer, "Expat %d.%d.%d", XML_MAJOR_VERSION,
                 XML_MINOR_VERSION, XML_MICRO_VERSION);
         return PyString_FromString(buffer);
+    } else if (name[0] == 'C') {
+	/* taken (almost) verbatim from pyexpat.c. */
+        if (strcmp(name, "CurrentLineNumber") == 0)
+            return PyInt_FromLong((long)
+                                  EXPAT(GetCurrentLineNumber)(self->parser));
+        if (strcmp(name, "CurrentColumnNumber") == 0)
+            return PyInt_FromLong((long)
+                                  EXPAT(GetCurrentColumnNumber)(self->parser));
+        if (strcmp(name, "CurrentByteIndex") == 0)
+            return PyInt_FromLong((long)
+                                  EXPAT(GetCurrentByteIndex)(self->parser));
+        PyErr_SetString(PyExc_AttributeError, name);
+        return NULL;
     } else {
         PyErr_SetString(PyExc_AttributeError, name);
         return NULL;