Merge pull request #190 from dotcloud/189-broken_env_tty_mode-fix

#189 Fix the env in TTY mode

container.go

@@ -258,8 +258,9 @@ func (container *Container) Start() error {
 
 	var err error
 	if container.Config.Tty {
-		container.cmd.Env = append(container.Config.Env,
-			"TERM=xterm",
+		container.cmd.Env = append(
+			[]string{"TERM=xterm"},
+			container.cmd.Env...,
 		)
 		err = container.startPty()
 	} else {