Erase the background of an image

Hello, I am trying to learn how to “cut” the background off of an image…

For example… I import a jpg of a server case into flash mx…

I dont need the white background that is on the image…
I just want the case with a transparent background…

I thought I would be able to cut around the image…
or erase just the white etc…

Anyone know how this is done in Flash?

Thank You.