The grub2 configuration file in Fedora 16 can have one or menuentrys
in a submenu, with configuration of the form
submenu "Xen 4.1" {
menuentry ... {
...
}
}
(this example occurs when the xen hypervisor is installed on the guest)
Ignore the submenu line and the corresponding } 
Signed-off-by: Michael Young <m.a.young@xxxxxxxxxxxx>

--- a/tools/pygrub/src/GrubConf.py	2011-10-17 21:26:48.000000000 +0100
+++ b/tools/pygrub/src/GrubConf.py	2011-10-17 21:46:00.000000000 +0100
@@ -368,6 +368,7 @@
         in_function = False
         img = None
         title = ""
+        menu_level=0
         for l in lines:
             l = l.strip()
             # skip blank lines
@@ -394,10 +395,18 @@
                 img = []
                 title = title_match.group(1)
                 continue
-            
+
+            if l.startswith("submenu"):
+                menu_level += 1
+                continue
+
             if l.startswith("}"):
                 if img is None:
-                    raise RuntimeError, "syntax error: closing brace without menuentry"
+                    if menu_level > 0:
+                        menu_level -= 1
+                        continue
+                    else:
+                        raise RuntimeError, "syntax error: closing brace without menuentry"
 
                 self.add_image(Grub2Image(title, img))
                 img = None