--- kdesu-5.5.0/src/kdesu_stub.c~	2015-02-13 16:53:30.000000000 +0300
+++ kdesu-5.5.0/src/kdesu_stub.c	2015-02-13 17:01:21.720000000 +0300
@@ -266,6 +266,7 @@ int main()
         exit(1);
     }
     xsetenv("HOME", pw->pw_dir);
+    xsetenv("USER", pw->pw_name);
 
     /* New user won't be able to connect it anyway. */
     unsetenv("DBUS_SESSION_BUS_ADDRESS");
@@ -308,6 +309,7 @@ int main()
             exit(1);
         }
         xsetenv("HOME", pw->pw_dir);
+        xsetenv("USER", pw->pw_name);
     }
 
     /* Handle display */