diff --git a/src/libprs500/devices/__init__.py b/src/libprs500/devices/__init__.py
index 5391abc7c1..c96437545b 100644
--- a/src/libprs500/devices/__init__.py
+++ b/src/libprs500/devices/__init__.py
@@ -15,3 +15,22 @@
 '''
 Device drivers.
 '''
+import time
+
+DAY_MAP   = dict(Sun=0, Mon=1, Tue=2, Wed=3, Thu=4, Fri=5, Sat=6)
+MONTH_MAP = dict(Jan=1, Feb=2, Mar=3, Apr=4, May=5, Jun=6, Jul=7, Aug=8, Sep=9, Oct=10, Nov=11, Dec=12) 
+INVERSE_DAY_MAP = dict(zip(DAY_MAP.values(), DAY_MAP.keys()))
+INVERSE_MONTH_MAP = dict(zip(MONTH_MAP.values(), MONTH_MAP.keys()))
+
+def strptime(src):
+    src = src.strip()
+    src = src.split()
+    src[0] = str(DAY_MAP[src[0][:-1]])+','
+    src[2] = str(MONTH_MAP[src[2]])
+    return time.strptime(' '.join(src), '%w, %d %m %Y %H:%M:%S %Z')
+
+def strftime(epoch):
+    src = time.strftime("%w, %d %m %Y %H:%M:%S GMT", time.gmtime(epoch)).split()
+    src[0] = INVERSE_DAY_MAP[int(src[0][:-1])]+','
+    src[2] = INVERSE_MONTH_MAP[int(src[2])]
+    return ' '.join(src)
\ No newline at end of file
diff --git a/src/libprs500/devices/prs500/books.py b/src/libprs500/devices/prs500/books.py
index 7c72cc8cb1..7c11b9f799 100644
--- a/src/libprs500/devices/prs500/books.py
+++ b/src/libprs500/devices/prs500/books.py
@@ -19,9 +19,10 @@ in the reader cache.
 import xml.dom.minidom as dom
 from base64 import b64decode as decode
 from base64 import b64encode as encode
-import time, re
+import re
 
 from libprs500.devices.interface import BookList as _BookList
+from libprs500.devices import strftime, strptime
 
 MIME_MAP   = { \
                         "lrf":"application/x-sony-bbeb", \
@@ -54,6 +55,7 @@ class book_metadata_field(object):
 
 class Book(object):
     """ Provides a view onto the XML element that represents a book """
+    
     title        = book_metadata_field("title")
     authors      = book_metadata_field("author", \
                             formatter=lambda x: x if x and x.strip() else "Unknown")
@@ -63,9 +65,7 @@ class Book(object):
     sourceid     = book_metadata_field("sourceid", formatter=int)
     size         = book_metadata_field("size", formatter=int)
     # When setting this attribute you must use an epoch
-    datetime     = book_metadata_field("date", \
-                           formatter=lambda x:  time.strptime(x.strip(), "%a, %d %b %Y %H:%M:%S %Z"), 
-                           setter=lambda x: time.strftime("%a, %d %b %Y %H:%M:%S GMT", time.gmtime(x)))
+    datetime     = book_metadata_field("date", formatter=strptime, setter=strftime)
     @apply
     def title_sorter():
         doc = '''String to sort the title. If absent, title is returned'''