Glossy buttons in Flex 3

Any ideas how to create a button class that looks something like this:

Taken from this tutorial page. I'm struggling to figure out what combination of filters I need to use to achieve the glossy effect.

The rounded corners and bevel/glow effect are simple enough. But how can I add a gloss gradient over only the top half of t开发者_StackOverflow中文版he button?

Use this App --> http://jirox.net/AsButtonGen/

Found it. Degrafa has a Button Loader thing that does this exactly.

Open source too.