Index: execunix.c
===================================================================
--- execunix.c	(revision 39453)
+++ execunix.c	(working copy)
@@ -211,6 +211,17 @@
             else
                 dup2(err[1], STDERR_FILENO);
 
+            /* Make this process a session leader
+             * so that when we kill it, all child
+             * processes of this process are terminated
+             * as well.
+             *
+             * we use kill(-pid, SIGKILL) to kill the
+             * session leader and all children of this
+             * session.
+             */
+            setsid();
+
 	    execvp( argv[0], argv );
 	    _exit(127);
 	}
@@ -367,7 +378,7 @@
             struct tms buf;
             clock_t current = times(&buf);
             if (globs.timeout <= (current-cmdtab[i].start_time)/tps) {
-                kill(cmdtab[i].pid, SIGKILL);
+                kill(-cmdtab[i].pid, SIGKILL);
                 cmdtab[i].exit_reason = EXIT_TIMEOUT;
             }
         }