diff --git a/kernel/system/do_copy.c b/kernel/system/do_copy.c
index 716ec1a85..1dd722490 100644
--- a/kernel/system/do_copy.c
+++ b/kernel/system/do_copy.c
@@ -30,6 +30,7 @@ register message *m_ptr;	/* pointer to request message */
   phys_bytes bytes;		/* number of bytes to copy */
   int i;
 
+#if 0
   if (m_ptr->m_source != 0 && m_ptr->m_source != 1 &&
 	m_ptr->m_source != 2 && m_ptr->m_source != 3)
   {
@@ -46,6 +47,7 @@ register message *m_ptr;	/* pointer to request message */
 			m_ptr->CP_DST_SPACE);
 	}
   }
+#endif
 
   /* Dismember the command message. */
   vir_addr[_SRC_].proc_nr_e = m_ptr->CP_SRC_ENDPT;