Outer glow not working properly

Hi. I'm using Photoshop CS3 and have an issue with outer glow. The outer glow works on a transparent (although the colour is much lighter) and black background, but won't show up on a white background.

Tried various other colours out of interest and you can see there's a glow, but it's not the correct colour, it seems to be a lighter shade of the background colour.

It also refuses to do a gradient outer glow. Whenever I select it and click ok it just changes it back to solid colour.

I tried closing and opening Photoshop and when that didn't work I tried restarting my computer, but I still have the same issue. I tried a new document, but it does the same.

Why will it not work on a white background? Is there any way to resolve this issue?

Thanks.