- If you ask me both (expat and libxml) are not really accurate about byte

positions and columns...however the line number information is now
  correct for both so for the moment we live with the situation that they
  return different byte and column information.

ext/xml/tests/bug26614.phpt

@@ -1,5 +1,7 @@
 --TEST--
 Bug #26614 (CDATA sections skipped on line count)
+--SKIPIF--
+<?php if (defined("LIBXML_VERSION")) die('skip expat test'); ?>
 --FILE--
 <?php
 /*

ext/xml/tests/bug26614_libxml.phpt

@@ -0,0 +1,90 @@
+--TEST--
+Bug #26614 (CDATA sections skipped on line count)
+--SKIPIF--
+<?php if (!defined("LIBXML_VERSION")) die('skip libxml2 test'); ?>
+--FILE--
+<?php
+/*
+this test works fine with Expat but fails with libxml
+which we now use as default
+
+further investigation has shown that not only line count
+is skippet on CDATA sections but that libxml does also
+show different column numbers and byte positions depending
+on context and in opposition to what one would expect to
+see and what good old Expat reported just fine ...
+*/
+
+$xmls = array();
+
+// Case 1: CDATA Sections
+$xmls["CDATA"] ='<?xml version="1.0" encoding="iso-8859-1" ?>
+<data>
+<![CDATA[
+multi
+line 
+CDATA
+block
+]]>
+</data>';
+
+// Case 2: replace some characters so that we get comments instead
+$xmls["Comment"] ='<?xml version="1.0" encoding="iso-8859-1" ?>
+<data>
+<!-- ATA[
+multi
+line 
+CDATA
+block
+-->
+</data>';
+
+// Case 3: replace even more characters so that only textual data is left 
+$xmls["Text"] ='<?xml version="1.0" encoding="iso-8859-1" ?>
+<data>
+-!-- ATA[
+multi
+line 
+CDATA
+block
+---
+</data>';
+
+function startElement($parser, $name, $attrs) {
+    printf("<$name> at line %d, col %d (byte %d)\n",
+		       xml_get_current_line_number($parser),
+		       xml_get_current_column_number($parser),
+		       xml_get_current_byte_index($parser));
+}
+
+function endElement($parser, $name) {
+    printf("</$name> at line %d, col %d (byte %d)\n",
+		       xml_get_current_line_number($parser),
+		       xml_get_current_column_number($parser),
+		       xml_get_current_byte_index($parser));
+}
+
+function characterData($parser, $data) {
+  // dummy 
+}
+
+foreach ($xmls as $desc => $xml) {
+  echo "$desc\n";
+	$xml_parser = xml_parser_create();
+	xml_set_element_handler($xml_parser, "startElement", "endElement");
+	xml_set_character_data_handler($xml_parser, "characterData");
+	if (!xml_parse($xml_parser, $xml, true)) 
+		echo "Error: ".xml_error_string(xml_get_error_code($xml_parser))."\n";
+	xml_parser_free($xml_parser);
+}
+?>
+--EXPECT--
+CDATA
+<DATA> at line 2, col 6 (byte 9)
+</DATA> at line 9, col 8 (byte 56)
+Comment
+<DATA> at line 2, col 6 (byte 9)
+</DATA> at line 9, col 8 (byte 56)
+Text
+<DATA> at line 2, col 6 (byte 9)
+</DATA> at line 9, col 8 (byte 56)