Clutch cable problem (ets 250)

[philtrophysport]

Out for a ride today taking advantage of the reasonable weather etc,suddenly my clutch lever goes all slack on me,i initially think its a broken cable but on closer inspection I see that the nipple holder at the engine end has unscrewed itself completely leaving the cable clutching at fresh air,is there a foolproof way of attaching this holder to its threaded anchor so that it cant work its way loose so easily, when I screwed it back on I couldn't really tighten it ,so it could still theoretically unscrew again ... am I missing something?
Thanks for any advice ...Phil.

[radiograf]

Try a thread locking compound such as Lock and Seal from Loctite.