diff --git a/execute_cmd.h b/execute_cmd.h
--- a/execute_cmd.h
+++ b/execute_cmd.h
@@ -37,6 +37,9 @@ struct func_array_state
   };
 #endif
 
+/* Variables delared in execute_cmd.c, used by many other files */
+extern int executing_command_builtin;
+
 extern struct fd_bitmap *new_fd_bitmap __P((int));
 extern void dispose_fd_bitmap __P((struct fd_bitmap *));
 extern void close_fd_bitmap __P((struct fd_bitmap *));
diff --git a/subst.c b/subst.c
--- a/subst.c
+++ b/subst.c
@@ -10676,11 +10676,12 @@ expand_word_list_internal (list, eflags)
 		  tint = do_word_assignment (temp_list->word, 0);
 		  this_command_name = savecmd;
 		  /* Variable assignment errors in non-interactive shells
-		     running in Posix.2 mode cause the shell to exit. */
+		     running in Posix.2 mode cause the shell to exit, unless 
+		     they are being run by the `command' builtin. */
 		  if (tint == 0)
 		    {
 		      last_command_exit_value = EXECUTION_FAILURE;
-		      if (interactive_shell == 0 && posixly_correct)
+		      if (interactive_shell == 0 && posixly_correct && executing_command_builtin == 0)
 			exp_jump_to_top_level (FORCE_EOF);
 		      else
 			exp_jump_to_top_level (DISCARD);