The first one: basically when you use the eraser brush, you can't erase the first row and column of pixels
<img src="https://dl.dropbox.com/u/23551572/C2/Report/bugs/imageEditor/border1.png" border="0" />
The second one: when you use the line tool with smooth mode active, the first row and column of pixels gets blurred with alpha
<img src="https://dl.dropbox.com/u/23551572/C2/Report/bugs/imageEditor/border2.png" border="0" />
Maybe it's graphic card related bug so here's my spec:
OS: Windows 2008 server r2 (64-bit)
Graphic Card: Nvidia GeForce GTX 460