Relative image resizing?

[mrSimon]

.narrowcolumn img {
max-width: 100%;
}

I've applied a max-width property to all 'img' tag's within a container, to ensure they do not overflow past it. However, in some browsers, the height isn't resized at a relative ratio.

IE

Real image
1000x800

Rescaled image
Target: 500x400
Some browsers: 500x800

Screenshot (http://87.6.21.209/safaritest/1178880980-full.jpg)

Is there any way to fix this?

[dbldutch]

Every browsers does not support "max-width" or "min-width".