diff -up mozilla-esr24/config/nsinstall.py.format mozilla-esr24/config/nsinstall.py
--- mozilla-esr24/config/nsinstall.py.format    2014-05-22 10:00:35.150360916 +0200
+++ mozilla-esr24/config/nsinstall.py   2014-05-22 10:12:25.492360916 +0200
@@ -38,7 +38,7 @@ def _nsinstall_internal(argv):
   # The remaining arguments are not used in our tree, thus they're not
   # implented.
   def BadArg(option, opt, value, parser):
-    parser.error('option not supported: {0}'.format(opt))
+    parser.error('option not supported: %s' % opt)
     
   p.add_option('-C', action="callback", metavar="CWD",
                callback=BadArg,
@@ -55,8 +55,8 @@ def _nsinstall_internal(argv):
     try:
       options.m = int(options.m, 8)
     except:
-      sys.stderr.write('nsinstall: {0} is not a valid mode\n'
-                       .format(options.m))
+      sys.stderr.write('nsinstall: %s: is not a valid mode\n'
+                       % options.m)
       return 1
 
   # just create one directory?
@@ -64,7 +64,7 @@ def _nsinstall_internal(argv):
     dir = os.path.abspath(dir)
     if os.path.exists(dir):
       if not os.path.isdir(dir):
-        sys.stderr.write('nsinstall: {0} is not a directory'.format(dir)+"\n")
+        sys.stderr.write('nsinstall: %s is not a directory' % dir+"\n")
         return 1
       if mode:
         os.chmod(dir, mode)
@@ -79,7 +79,7 @@ def _nsinstall_internal(argv):
       # We might have hit EEXIST due to a race condition (see bug 463411) -- try again once
       if try_again:
         return maybe_create_dir(dir, mode, False)
-      print("nsinstall: failed to create directory {0}: {1}".format(dir, e))
+      print("nsinstall: failed to create directory %s : %s" % (dir,e))
       return 1
     else:
       return 0

diff -up mozilla-esr24/js/src/config/nsinstall.py.python2 mozilla-esr24/js/src/config/nsinstall.py
--- mozilla-esr24/js/src/config/nsinstall.py.python2    2014-05-22 10:00:35.150360916 +0200
+++ mozilla-esr24/js/src/config/nsinstall.py   2014-05-22 10:12:25.492360916 +0200
@@ -38,7 +38,7 @@ def _nsinstall_internal(argv):
   # The remaining arguments are not used in our tree, thus they're not
   # implented.
   def BadArg(option, opt, value, parser):
-    parser.error('option not supported: {0}'.format(opt))
+    parser.error('option not supported: %s' % opt)
     
   p.add_option('-C', action="callback", metavar="CWD",
                callback=BadArg,
@@ -55,8 +55,8 @@ def _nsinstall_internal(argv):
     try:
       options.m = int(options.m, 8)
     except:
-      sys.stderr.write('nsinstall: {0} is not a valid mode\n'
-                       .format(options.m))
+      sys.stderr.write('nsinstall: %s: is not a valid mode\n'
+                       % options.m)
       return 1
 
   # just create one directory?
@@ -64,7 +64,7 @@ def _nsinstall_internal(argv):
     dir = os.path.abspath(dir)
     if os.path.exists(dir):
       if not os.path.isdir(dir):
-        sys.stderr.write('nsinstall: {0} is not a directory'.format(dir)+"\n")
+        sys.stderr.write('nsinstall: %s is not a directory' % dir+"\n")
         return 1
       if mode:
         os.chmod(dir, mode)
@@ -79,7 +79,7 @@ def _nsinstall_internal(argv):
       # We might have hit EEXIST due to a race condition (see bug 463411) -- try again once
       if try_again:
         return maybe_create_dir(dir, mode, False)
-      print("nsinstall: failed to create directory {0}: {1}".format(dir, e))
+      print("nsinstall: failed to create directory %s : %s" % (dir,e))
       return 1
     else:
       return 0