diff --git a/src/calibre/__init__.py b/src/calibre/__init__.py
index 79dc659f34..2bbf18d9e0 100644
--- a/src/calibre/__init__.py
+++ b/src/calibre/__init__.py
@@ -284,39 +284,7 @@ def launch(path_or_url):
         path_or_url = 'file:'+path_or_url
     QDesktopServices.openUrl(QUrl(path_or_url))
 
-def relpath(target, base=os.curdir):
-    """
-    Return a relative path to the target from either the current dir or an optional base dir.
-    Base can be a directory specified either as absolute or relative to current dir.
-    """
-
-    #if not os.path.exists(target):
-    #    raise OSError, 'Target does not exist: '+target
-    if target == base:
-        raise ValueError('target and base are both: %s'%target)
-    if not os.path.isdir(base):
-        raise OSError, 'Base is not a directory or does not exist: '+base
-
-    base_list = (os.path.abspath(base)).split(os.sep)
-    target_list = (os.path.abspath(target)).split(os.sep)
-
-    # On the windows platform the target may be on a completely different drive from the base.
-    if iswindows and base_list[0].upper() != target_list[0].upper():
-        raise OSError, 'Target is on a different drive to base. Target: '+repr(target)+', base: '+repr(base)
-
-    # Starting from the filepath root, work out how much of the filepath is
-    # shared by base and target.
-    for i in range(min(len(base_list), len(target_list))):
-        if base_list[i] != target_list[i]: break
-    else:
-        # If we broke out of the loop, i is pointing to the first differing path elements.
-        # If we didn't break out of the loop, i is pointing to identical path elements.
-        # Increment i so that in all cases it points to the first differing path elements.
-        i+=1
-
-    rel_list = [os.pardir] * (len(base_list)-i) + target_list[i:]
-    return os.path.join(*rel_list)
-
+relpath = os.path.relpath
 _spat = re.compile(r'^the\s+|^a\s+|^an\s+', re.IGNORECASE)
 def english_sort(x, y):
     '''
diff --git a/src/calibre/ebooks/metadata/opf2.py b/src/calibre/ebooks/metadata/opf2.py
index 4d1af0ee75..f801dbf65c 100644
--- a/src/calibre/ebooks/metadata/opf2.py
+++ b/src/calibre/ebooks/metadata/opf2.py
@@ -15,7 +15,6 @@ from lxml import etree
 from dateutil import parser
 
 from calibre.ebooks.chardet import xml_to_unicode
-from calibre import relpath
 from calibre.constants import __appname__, __version__
 from calibre.ebooks.metadata.toc import TOC
 from calibre.ebooks.metadata import MetaInformation, string_to_authors
@@ -86,8 +85,8 @@ class Resource(object):
         if self.path == basedir:
             return ''+frag
         try:
-            rpath = relpath(self.path, basedir)
-        except OSError: # On windows path and basedir could be on different drives
+            rpath = os.path.relpath(self.path, basedir)
+        except ValueError: # On windows path and basedir could be on different drives
             rpath = self.path
         if isinstance(rpath, unicode):
             rpath = rpath.encode('utf-8')
@@ -560,7 +559,7 @@ class OPF(object):
                 has_path = True
                 break
         if not has_path:
-            href = relpath(path, self.base_dir).replace(os.sep, '/')
+            href = os.path.relpath(path, self.base_dir).replace(os.sep, '/')
             item = self.create_manifest_item(href, media_type)
             manifest = self.manifest_ppath(self.root)[0]
             manifest.append(item)
diff --git a/src/calibre/ebooks/mobi/writer.py b/src/calibre/ebooks/mobi/writer.py
index 7d63744e57..f63eaa0940 100644
--- a/src/calibre/ebooks/mobi/writer.py
+++ b/src/calibre/ebooks/mobi/writer.py
@@ -511,7 +511,7 @@ class MobiWriter(object):
         indxt, indxt_count, indices, last_name = \
                 self._generate_indxt(ctoc)
         if last_name is None:
-            self._oeb.log.warn('Input document has no TOC. No idex generated.')
+            self._oeb.log.warn('Input document has no TOC. No index generated.')
             return
 
         indx1 = StringIO()
@@ -628,8 +628,8 @@ class MobiWriter(object):
         self._last_toc_entry = None
         ctoc = StringIO()
 
-        def add_node(node, cls):
-            t = node.title
+        def add_node(node, cls, title=None):
+            t = node.title if title is None else title
             if t and t.strip():
                 t = t.strip()
                 if not isinstance(t, unicode):
@@ -640,8 +640,10 @@ class MobiWriter(object):
                 self._ctoc_name_map[node] = t
                 ctoc.write(decint(len(t), DECINT_FORWARD)+t)
 
+        first = True
         for child in toc.iter():
-            add_node(child, 'chapter')
+            add_node(child, 'chapter', title='Title Page' if first else None)
+            first = False
 
         return align_block(ctoc.getvalue())
 
@@ -842,7 +844,8 @@ class MobiWriter(object):
         if INDEXING:
             # Write unknown EXTH records as 0s
             for code, size in [(204,4), (205,4), (206,4), (207,4), (300,40)]:
-                exth.write(pack('>I', code)+'\0'*size)
+                exth.write(pack('>II', code, 8+size)+'\0'*size)
+                nrecs += 1
         exth = exth.getvalue()
         trail = len(exth) % 4
         pad = '\0' * (4 - trail) # Always pad w/ at least 1 byte
diff --git a/src/calibre/gui2/main.py b/src/calibre/gui2/main.py
index 0a77839ce1..bdc4568dce 100644
--- a/src/calibre/gui2/main.py
+++ b/src/calibre/gui2/main.py
@@ -1670,7 +1670,7 @@ class Main(MainWindow, Ui_MainWindow, DeviceGUI):
     def update_found(self, version):
         os = 'windows' if iswindows else 'osx' if isosx else 'linux'
         url = 'http://%s.kovidgoyal.net/download_%s'%(__appname__, os)
-        self.latest_version = '<br>'+_('<span style="color:red; font-weight:bold">'
+        self.latest_version = '<br>' + _('<span style="color:red; font-weight:bold">'
                 'Latest version: <a href="%s">%s</a></span>')%(url, version)
         self.vanity.setText(self.vanity_template%\
                 (dict(version=self.latest_version,