You're right, it has happened to me before. Sometimes, the temperature is shown as 253C. But 90% of the time, it is around 34C or so.
Now the temperature is back to 34C and the hard drive imminent failure message is gone.
Instead, I get this message:
"Warning!
Active Smart detected attribute changing in the drive WDC WD2500KS 250.01GB.
Show more information?"
I'll just buy some more dvd+rs today just to be on the safe side. I'll still back up my data.
Should I be concerned about my hard drive?