diff --git a/Makefile b/Makefile
index 1abffcec66..399c086d95 100644
--- a/Makefile
+++ b/Makefile
@@ -33,11 +33,17 @@ pictureflow :
 	cd ../PyQt && \
 	mkdir -p .build && \
 	cd .build && rm -f * && \
-	python ../configure.py && make && \
+	${PYTHON} ../configure.py && make && \
 	cd ../../../../../.. && \
 	cp src/calibre/gui2/pictureflow/PyQt/.build/pictureflow.so src/calibre/plugins/ && \
 	rm -rf src/calibre/gui2/pictureflow/.build rm -rf src/calibre/gui2/pictureflow/PyQt/.build
 
+lzx :
+	mkdir -p src/calibre/plugins && rm -f src/calibre/plugins/*pictureflow* && \
+    cd src/calibre/utils/lzx && mkdir .build && cd .build && \
+    ${PYTHON} ../configure.py && make && cd - && \
+    cp src/calibre/utils/lzx/.build/lzx.so src/calibre/plugins/ && \
+    rm -rf src/calibre/utils/lzx/.build/
 
 pot :
 	cd src/calibre/translations && ${PYTHON} __init__.py pot
diff --git a/src/calibre/__init__.py b/src/calibre/__init__.py
index b52a2bcbc8..2237024963 100644
--- a/src/calibre/__init__.py
+++ b/src/calibre/__init__.py
@@ -477,13 +477,16 @@ class Settings(QSettings):
                            'kovidgoyal.net', name)
         
     def get(self, key, default=None):
-        key = str(key)
-        if not self.contains(key):
+        try:
+            key = str(key)
+            if not self.contains(key):
+                return default
+            val = str(self.value(key, QVariant()).toByteArray())
+            if not val:
+                return None
+            return cPickle.loads(val)
+        except:
             return default
-        val = str(self.value(key, QVariant()).toByteArray())
-        if not val:
-            return None
-        return cPickle.loads(val)
     
     def set(self, key, val):
         val = cPickle.dumps(val, -1)
diff --git a/src/calibre/ebooks/lrf/html/convert_from.py b/src/calibre/ebooks/lrf/html/convert_from.py
index e1014d69dd..b118520b82 100644
--- a/src/calibre/ebooks/lrf/html/convert_from.py
+++ b/src/calibre/ebooks/lrf/html/convert_from.py
@@ -1453,6 +1453,7 @@ class HTMLConverter(object, LoggingInterface):
                 self.page_break_found = True
 
                 if self.options.add_chapters_to_toc:
+                    self.current_block.must_append = True
                     self.extra_toc_entries.append((self.get_text(tag,
                         limit=1000), self.current_block))
 
@@ -1666,6 +1667,7 @@ class HTMLConverter(object, LoggingInterface):
                         self.page_break_found = True
 
                         if self.options.add_chapters_to_toc:
+                            self.current_block.must_append = True
                             self.extra_toc_entries.append((self.get_text(tag,
                                 limit=1000), self.current_block))
                 
diff --git a/src/calibre/gui2/main.py b/src/calibre/gui2/main.py
index d85acb9dcb..fa3896a4ca 100644
--- a/src/calibre/gui2/main.py
+++ b/src/calibre/gui2/main.py
@@ -40,7 +40,6 @@ from calibre.gui2.dialogs.search import SearchDialog
 from calibre.gui2.dialogs.user_profiles import UserProfiles
 from calibre.gui2.dialogs.choose_format import ChooseFormatDialog
 from calibre.gui2.dialogs.book_info import BookInfo
-from calibre.library.database import DatabaseLocked
 from calibre.ebooks.metadata.meta import set_metadata
 from calibre.ebooks.metadata import MetaInformation
 from calibre.ebooks import BOOK_EXTENSIONS
@@ -1247,12 +1246,7 @@ path_to_ebook to the database.
                                  '<p>%s is already running. %s</p>'%(__appname__, extra))
             return 1
         initialize_file_icon_provider()
-        try:
-            main = Main(single_instance, opts)
-        except DatabaseLocked, err:
-            QMessageBox.critical(None, 'Cannot Start '+__appname__,
-            '<p>Another program is using the database. <br/>Perhaps %s is already running?<br/>If not try deleting the file %s'%(__appname__, err.lock_file_path))
-            return 1
+        main = Main(single_instance, opts)
         sys.excepthook = main.unhandled_exception
         if len(args) > 1:
             main.add_filesystem_book(args[1])
diff --git a/src/calibre/library/database.py b/src/calibre/library/database.py
index d3f4654969..006438746b 100644
--- a/src/calibre/library/database.py
+++ b/src/calibre/library/database.py
@@ -31,47 +31,9 @@ class Concatenate(object):
             return self.ans[:-len(self.sep)]
         return self.ans
 
-_lock_file = None
-class DatabaseLocked(Exception):
-    
-    def __init__(self, msg, lock_file_path):
-        Exception.__init__(self, msg)
-        self.lock_file_path = lock_file_path
-
-def _lock(path):
-    path = os.path.join(os.path.dirname(path), '.'+os.path.basename(path)+'.lock')
-    global _lock_file
-    if _lock_file is not None:
-        raise DatabaseLocked('Database already locked in this instance.', _lock_file.name)
-    try:
-        _lock_file = open(path, 'wb')
-    except IOError:
-        raise DatabaseLocked('Database in use by another instance', path)
-    try:
-        import fcntl, errno
-        try:
-            fcntl.lockf(_lock_file.fileno(), fcntl.LOCK_EX|fcntl.LOCK_NB)
-        except IOError, err:
-            path = _lock_file.name
-            _lock_file = None
-            if err.errno in (errno.EACCES, errno.EAGAIN):
-                raise DatabaseLocked('Database in use by another instance', path)
-    except ImportError:
-        try:
-            import msvcrt
-            try:
-                msvcrt.locking(_lock_file.fileno(), msvcrt.LK_NBLCK, 1)
-            except IOError:
-                path = _lock_file.name
-                _lock_file = None
-                raise DatabaseLocked('Database in use by another instance', path)
-        except ImportError:
-            pass
-
 def _connect(path):
     if isinstance(path, unicode):
         path = path.encode('utf-8')
-    #_lock(path)
     conn =  sqlite.connect(path, detect_types=sqlite.PARSE_DECLTYPES|sqlite.PARSE_COLNAMES)
     conn.row_factory = lambda cursor, row : list(row)
     conn.create_aggregate('concat', 1, Concatenate)
@@ -794,14 +756,6 @@ ALTER TABLE books ADD COLUMN isbn TEXT DEFAULT "" COLLATE NOCASE;
         conn.commit()
         
         
-    def __del__(self):
-        global _lock_file
-        import os
-        if _lock_file is not None:
-            _lock_file.close()
-            if os.path.exists(_lock_file.name):
-                os.unlink(_lock_file.name) 
-    
     def __init__(self, dbpath, row_factory=False):
         self.dbpath = dbpath
         self.conn = _connect(dbpath)
diff --git a/src/calibre/manual/faq.rst b/src/calibre/manual/faq.rst
index cb381cb8aa..d130bd9a1b 100644
--- a/src/calibre/manual/faq.rst
+++ b/src/calibre/manual/faq.rst
@@ -133,10 +133,9 @@ The graphical user interface of |app| is not starting on Windows?
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 If you've never used the graphical user interface before, try deleting the file library1.db (it will be somewhere under :file:`C:\\Documents and Settings` on Windows XP and :file:`C:\\Users` on Windows Vista. If that doesn't fix the problem, locate the file calibre.log (in the same places as library1.db) and post its contents in a help message on the `Forums <http://calibre.kovidgoyal.net/discussion>`_. If you can't find either file, try using the windows find feature to search for them. If the files dont exist on your system, try the following:
     
-Start a command prompt (press the windows key and R and type cmd.exe in the run dialog). At the command prompt type the command `calibre-debug` and press enter. You will se a new, green prompt. At theis prompt, type the following two lines::
+Start a command prompt (press the windows key and R and type cmd.exe in the run dialog). At the command prompt type the following command and press Enter::
 
-    from calibre.gui2.main import main
-    main()
+    calibre-debug -c "from calibre.gui2.main import main; main()"
 
 Post any output you see when asking for help.