diff --git a/osx_installer.py b/osx_installer.py
index 810ba6e4b5..ba49c9c622 100644
--- a/osx_installer.py
+++ b/osx_installer.py
@@ -244,7 +244,7 @@ def main():
                          'iconfile' : 'icons/library.icns',
                          'frameworks': ['libusb.dylib', 'libunrar.dylib'],
                          'includes' : ['sip', 'pkg_resources', 'PyQt4.QtSvg', 
-                                       'mechanize', 'ClientForm', 'usbobserver'],
+                                       'mechanize', 'ClientForm', 'usbobserver', 'genshi'],
                          'packages' : ['PIL', 'Authorization', 'rtf2xml', 'lxml'],
                          'excludes' : ['pydoc'],
                          'plist'    : { 'CFBundleGetInfoString' : '''libprs500, an E-book management application.'''
diff --git a/windows_installer.py b/windows_installer.py
index 4cfd8ebb34..d9e7f01b10 100644
--- a/windows_installer.py
+++ b/windows_installer.py
@@ -465,7 +465,7 @@ def main():
                                   'includes'  : ['sip', 'pkg_resources', 'PyQt4.QtSvg', 
                                                  'mechanize', 'ClientForm', 'wmi', 
                                                  'win32file', 'pythoncom', 'rtf2xml', 
-                                                 'lxml', 'lxml._elementpath'],                                
+                                                 'lxml', 'lxml._elementpath', 'genshi'],                                
                                   'packages'  : ['PIL'],
                                   'excludes'  : ["Tkconstants", "Tkinter", "tcl", 
                                                  "_imagingtk", "ImageTk", "FixTk",