diff --git a/src/calibre/ebooks/pdf/pdftohtml.py b/src/calibre/ebooks/pdf/pdftohtml.py
index 7aa9f4bcf2..96fb28e923 100644
--- a/src/calibre/ebooks/pdf/pdftohtml.py
+++ b/src/calibre/ebooks/pdf/pdftohtml.py
@@ -14,7 +14,7 @@ from calibre.ptempfile import PersistentTemporaryFile
 from calibre.constants import (isosx, iswindows, islinux, isbsd,
             filesystem_encoding)
 from calibre import CurrentDir
-from calibre.utils.cleantext import clean_ascii_chars
+from calibre.utils.cleantext import clean_xml_chars
 
 PDFTOHTML = 'pdftohtml'
 popen = subprocess.Popen
@@ -125,7 +125,7 @@ def pdftohtml(output_dir, pdf_path, no_images, as_xml=False):
 
 def parse_outline(raw, output_dir):
     from lxml import etree
-    raw = clean_ascii_chars(xml_to_unicode(raw, strip_encoding_pats=True, assume_utf8=True)[0])
+    raw = clean_xml_chars(xml_to_unicode(raw, strip_encoding_pats=True, assume_utf8=True)[0])
     outline = etree.fromstring(raw).xpath('(//outline)[1]')
     if outline:
         from calibre.ebooks.oeb.polish.toc import TOC, create_ncx