diff --git a/src/calibre/manual/gui.rst b/src/calibre/manual/gui.rst
index dd0451c087..02018c0b02 100644
--- a/src/calibre/manual/gui.rst
+++ b/src/calibre/manual/gui.rst
@@ -208,19 +208,24 @@ You can build advanced search queries easily using the :guilabel:`Advanced Searc
 clicking the button |sbi|.
 
 Available fields for searching are: ``tag, title, author, publisher, series, rating cover, comments, format,
-isbn, date, pubdate, search``.
+isbn, date, pubdate, search, size``. To find the search name for a custom column, hover your mouse over the column header.
 
 The syntax for searching for dates and publication dates is::
 
     pubdate:>2000-1 Will find all books published after Jan, 2000
-    date:<=2000-1-3 Will find all books added to calibre beforre 3 Jan, 2000
+    date:<=2000-1-3 Will find all books added to calibre before 3 Jan, 2000
     pubdate:=2009 Will find all books published in 2009
 
+You can search for books that have a format of a certain size like this::
+
+    size:>1.1M Will find books with a format larger than 1.1MB
+    size:<=1K  Will find books with a format smaller than 1KB
+
 The special field ``search`` is used for saved searches. So if you save a search with the name
 "My spouse's books" you can enter ``search:"My spouses' books"`` in the search bar to reuse the saved
 search. More about saving searches, below.
 
-You can search for the absence or presnce of a filed using the specia "true" and "false" values. For example::
+You can search for the absence or presence of a field using the special "true" and "false" values. For example::
 
     cover:false Will give you all books without a cover
     series:true Will give you all books that belong to a series
diff --git a/src/calibre/utils/podofo/podofo.cpp b/src/calibre/utils/podofo/podofo.cpp
index d88e71628d..ace8c58c70 100644
--- a/src/calibre/utils/podofo/podofo.cpp
+++ b/src/calibre/utils/podofo/podofo.cpp
@@ -6,15 +6,10 @@
 #include <podofo.h>
 using namespace PoDoFo;
 
-class podofo_pdfmem_wrapper : public PdfMemDocument {
-    public:
-        inline void set_info(PdfInfo *i) { this->SetInfo(i); }
-};
-
 typedef struct {
     PyObject_HEAD
     /* Type-specific fields go here. */
-    podofo_pdfmem_wrapper *doc;
+    PdfMemDocument *doc;
 
 } podofo_PDFDoc;
 
@@ -33,7 +28,7 @@ podofo_PDFDoc_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
 
     self = (podofo_PDFDoc *)type->tp_alloc(type, 0);
     if (self != NULL) {
-        self->doc = new podofo_pdfmem_wrapper();
+        self->doc = new PdfMemDocument();
         if (self->doc == NULL) { Py_DECREF(self); return NULL; }
     }
 
@@ -171,6 +166,19 @@ podofo_convert_pystring(PyObject *py) {
     return ans;
 }
 
+static PdfString *
+podofo_convert_pystring_single_byte(PyObject *py) {
+    Py_UNICODE* u = PyUnicode_AS_UNICODE(py);
+    PyObject *s = PyUnicode_Encode(u, PyUnicode_GET_SIZE(py), "cp1252", "replace");
+    if (s == NULL) { PyErr_NoMemory(); return NULL; }
+    PdfString *ans = new PdfString(PyString_AS_STRING(s));
+    Py_DECREF(s);
+    if (ans == NULL) PyErr_NoMemory();
+    return ans;
+}
+
+
+
 static PyObject *
 podofo_PDFDoc_getter(podofo_PDFDoc *self, int field)
 {
@@ -219,7 +227,10 @@ podofo_PDFDoc_setter(podofo_PDFDoc *self, PyObject *val, int field) {
         PyErr_SetString(PyExc_Exception, "You must first load a PDF Document");
         return -1;
     }
-    PdfString *s = podofo_convert_pystring(val); 
+    PdfString *s = NULL;
+
+    if (self->doc->GetEncrypted()) s = podofo_convert_pystring_single_byte(val);
+    else s = podofo_convert_pystring(val); 
     if (s == NULL) return -1;
 
 
@@ -241,9 +252,6 @@ podofo_PDFDoc_setter(podofo_PDFDoc *self, PyObject *val, int field) {
             return -1;
     }
 
-
-    self->doc->set_info(info);
-
     return 0;
 }