How do I Create a "fill effects" background without using preset colors in PowerPoint 2007?

I had always used powerpoint 2003 or 2004(?) before... I now have a new laptop and consequently PP version. In the old PP all I had to do was click *format* *backround* *fill effects* and then i could choose my colors for gradient(the fade outs). Now I click format background and there is a fill effects option however under gradient there is no option to choose my own colors, it only contains the preset ones... which are extremely ugly... just sayin'. :) HELP!