Issue on displaying image in forum

Hi,

I installed advanced_forum module, and FCKEditor module.
With FCKEditor, I can upload images, and the images will displayed together with my text.
The problem is: when I upload images, which have sizes larger than the region holding the forum content, the images will be displayed with the original sizes, which will exceed the boder of the content box.

Any suggestions how to solve this problem? Thanks.(I know I can use FCKEditor to resize the image, but I just hope the web can handle the oversize situation automatically.)

Hang