Change Avatar problem

Hello,
To change Avatar in CjBlog is not convenient. I should need to justified the image before I can upload it to CjBlog or the image will not upload properly. BTW, the image uploaded to Avatar will change the ratio and then the picture will not useable.
I think facebook use a proper way for eveybody can change Avatar easily:
1. upload your image whatever its size or pixel
2. then you can select the part to suit the Avatar size
3. most importly, keep the image ratio (now CjBlog will change the ratio)

Hope you can modify this or users will not easy to change their Avatar and will cause the Blog not so user friendly.
Thanks for your regards,