diff -up src/module_list.py.orig src/module_list.py
--- src/module_list.py.orig	2015-04-03 15:10:36.432409060 -0300
+++ src/module_list.py	2015-04-03 15:10:46.240409436 -0300
@@ -2149,7 +2149,7 @@ ext_modules = [
 def is_package_installed(name):
     return False
 
-if is_package_installed('fes'):
+if 1:
     ext_modules.extend([
        Extension("sage.libs.fes",
                  ["sage/libs/fes.pyx"],