Temperature Guage - Under-reading ?

[snarfy]

Basicaly I start the car up and th thing gradually warms up. Thermostat opens and water then floods through the radiator. Fans eventually kick in and out accordingly. BUT the temp guage never seems to get higher than about 60degrees. Is this a know prb with the temp sender for the guage or is the guage funny or is it an..... earthing problem.....?
Oh and Happy Christmas and happy excess to everybody !
and Oh again... its a 99S Griff....must change that profile.