It's a 1gb sandisk. I backed up all my data from it onto my computer...and am probably going to buy another card soon. However, I was thinking... Would reformatting the card work?
problems

You can do that and it won't heart any thing. I reformatted after I had problems with my SD card. I have a back up know but I have been using the reformatted card for about 3 weeks now without any

Is there a way to reformat it in the phone or do I need to get a card reader and reformat it via my PC?

I posted a program somewhere in the apache forums to reformat card from the phone. it was a trial tho. I will see if I can't find that link for ya.
~mike

also you wont have to buy another card because you have 5 years of warranty on it.