diff --git a/session.vim b/session.vim
index 54fb6305c2..f2adf71de9 100644
--- a/session.vim
+++ b/session.vim
@@ -1,5 +1,5 @@
 " Project wide builtins
-let g:pyflakes_builtins += ["dynamic_property", "__", "P", "I", "lopen"]
+let g:pyflakes_builtins += ["dynamic_property", "__", "P", "I", "lopen", "icu_lower", "icu_upper", "icu_title"]
 
 python << EOFPY
 import os
diff --git a/setup/check.py b/setup/check.py
index 57c72e08c1..3e94b9dda1 100644
--- a/setup/check.py
+++ b/setup/check.py
@@ -63,7 +63,8 @@ class Check(Command):
 
     description = 'Check for errors in the calibre source code'
 
-    BUILTINS = ['_', '__', 'dynamic_property', 'I', 'P', 'lopen']
+    BUILTINS = ['_', '__', 'dynamic_property', 'I', 'P', 'lopen', 'icu_lower',
+            'icu_upper', 'icu_title']
     CACHE = '.check-cache.pickle'
 
     def get_files(self, cache):
diff --git a/src/calibre/ebooks/fb2/fb2ml.py b/src/calibre/ebooks/fb2/fb2ml.py
index 46861357e6..51bfaa7293 100644
--- a/src/calibre/ebooks/fb2/fb2ml.py
+++ b/src/calibre/ebooks/fb2/fb2ml.py
@@ -20,7 +20,7 @@ from calibre import prepare_string_for_xml
 from calibre.constants import __appname__, __version__
 from calibre.ebooks.oeb.base import XHTML, XHTML_NS, barename, namespace
 from calibre.ebooks.oeb.stylizer import Stylizer
-from calibre.ebooks.oeb.base import OEB_RASTER_IMAGES
+from calibre.ebooks.oeb.base import OEB_RASTER_IMAGES, OPF
 from calibre.utils.magick import Image
 
 class FB2MLizer(object):
@@ -85,8 +85,8 @@ class FB2MLizer(object):
         metadata['version'] = __version__
         metadata['date'] = '%i.%i.%i' % (datetime.now().day, datetime.now().month, datetime.now().year)
         metadata['lang'] = u''.join(self.oeb_book.metadata.lang) if self.oeb_book.metadata.lang else 'en'
-        metadata['id'] = '%s' % uuid.uuid4() 
-        
+        metadata['id'] = None
+
         author_parts = self.oeb_book.metadata.creator[0].value.split(' ')
         if len(author_parts) == 1:
             metadata['author_last'] = author_parts[0]
@@ -98,6 +98,15 @@ class FB2MLizer(object):
             metadata['author_middle'] = ' '.join(author_parts[1:-2])
             metadata['author_last'] = author_parts[-1]
 
+        identifiers = self.oeb_book.metadata['identifier']
+        for x in identifiers:
+            if x.get(OPF('scheme'), None).lower() == 'uuid' or unicode(x).startswith('urn:uuid:'):
+                metadata['id'] = unicode(x).split(':')[-1]
+                break
+        if metadata['id'] is None:
+            self.log.warn('No UUID identifier found')
+            metadata['id'] = str(uuid.uuid4()) 
+
         for key, value in metadata.items():
             metadata[key] = prepare_string_for_xml(value)
 
diff --git a/src/calibre/ebooks/mobi/langcodes.py b/src/calibre/ebooks/mobi/langcodes.py
index 723b619590..5d085906df 100644
--- a/src/calibre/ebooks/mobi/langcodes.py
+++ b/src/calibre/ebooks/mobi/langcodes.py
@@ -322,7 +322,7 @@ def iana2mobi(icode):
     while len(subtags) > 0:
         subtag = subtags.pop(0)
         if subtag not in langdict:
-            subtag = icu_title(subtag)
+            subtag = subtag.title()
         if subtag not in langdict:
             subtag = subtag.upper()
         if subtag in langdict:
diff --git a/src/calibre/utils/titlecase.py b/src/calibre/utils/titlecase.py
index cb0d840515..b85670f038 100755
--- a/src/calibre/utils/titlecase.py
+++ b/src/calibre/utils/titlecase.py
@@ -41,7 +41,6 @@ def titlecase(text):
     """
 
     def capitalize(w):
-        print 'in capitalize'
         w = icu_lower(w)
         w = w.replace(w[0], icu_upper(w[0]))
         return w