TD5 lumpy at start with white smoke

Hi. I seem to have an intermittent problem with my 1999 TD5. Fault only happens maybe once a week. It happened again this morning. Usual cold starting routine followed, i.e. wait for all the warning lights to go off before turning the key. When I started it today, a few of the lights came back on for a few seconds but most significantly the engine was clearly not running on all cylinders. There was also a lot of smelly white smoke coming out the back! After a minute or so of running the engine was running normally and no more smoke.

Could this be symptomatic of glow plug failure? RAVE doesn't seem to even acknowledge their presence let alone explain how to change them. I have read elsewhere that it is straightforward (albeit fiddly).

Any comments/thoughts anyone? Anything constructive much appreciated.