trouble changing gradient on buttons, can't get bright enough

[Soliloquy]

I'm having trouble changing colors to match my site on some of the tiny buttons. For example, I'm trying to change the colors of the buttons/lastpost.gif and other arrow buttons to a bright orange, but when I apply the gradient without a blend mode it goes over the edge of the button. When I apply it trying out various blend modes, it always comes out too dark, like this:
http://www.icecreamnewyork.com/forums/images/buttons/lastpost.gif
when I'm really trying for a brighter color like this:
http://www.icecreamnewyork.com/forums/images/statusicon/post_new.gif
can anyone advise me as to how to get the colors bright enough without getting rid of the shading and depth of the original?