diff -urN linux-2.4.18-wt4/arch/alpha/kernel/entry.S linux-2.4.18-wt4-alpha/arch/alpha/kernel/entry.S
--- linux-2.4.18-wt4/arch/alpha/kernel/entry.S	Sun Mar 31 21:34:16 2002
+++ linux-2.4.18-wt4-alpha/arch/alpha/kernel/entry.S	Sun Mar 31 22:10:24 2002
@@ -10,7 +10,7 @@
 
 #define SIGCHLD 20
 
-#define NR_SYSCALLS 382
+#define NR_SYSCALLS 384
 
 /*
  * These offsets must match with alpha_mv in <asm/machvec.h>.
@@ -1157,6 +1157,8 @@
 	.quad sys_readahead
 	.quad sys_ni_syscall			/* 380, sys_security */
 	.quad sys_tkill
+	.quad sys_new_s_context
+	.quad sys_set_ipv4root
 
 /* Remember to update everything, kids.  */
 .ifne (. - sys_call_table) - (NR_SYSCALLS * 8)
diff -urN linux-2.4.18-wt4/arch/alpha/kernel/ptrace.c linux-2.4.18-wt4-alpha/arch/alpha/kernel/ptrace.c
--- linux-2.4.18-wt4/arch/alpha/kernel/ptrace.c	Sat Dec  1 18:27:13 2001
+++ linux-2.4.18-wt4-alpha/arch/alpha/kernel/ptrace.c	Sun Mar 31 22:12:29 2002
@@ -271,7 +271,7 @@
 	if (child)
 		get_task_struct(child);
 	read_unlock(&tasklist_lock);
-	if (!child)
+	if (!child || child->s_context != current->s_context)
 		goto out_notsk;
 	if (request == PTRACE_ATTACH) {
 		ret = ptrace_attach(child);
diff -urN linux-2.4.18-wt4/include/asm-alpha/unistd.h linux-2.4.18-wt4-alpha/include/asm-alpha/unistd.h
--- linux-2.4.18-wt4/include/asm-alpha/unistd.h	Sun Mar 31 21:34:16 2002
+++ linux-2.4.18-wt4-alpha/include/asm-alpha/unistd.h	Sun Mar 31 22:08:29 2002
@@ -319,6 +319,8 @@
 #define __NR_readahead			379
 #define __NR_security			380 /* syscall for security modules */
 #define __NR_tkill			381
+#define __NR_new_s_context		382 /* for vservers */
+#define __NR_set_ipv4root		383 /* for vservers */
 
 #if defined(__GNUC__)