This article came in very handy in our project!

"Creating controls for .NET Compact Framework–based applications—which include transparency, gradients, and three-dimensional glass-like appearance—is well within reach today, using existing Microsoft Windows Mobile development tools. This article will demonstrate how to achieve transparency, gradients, and glass effects by extending existing .NET Compact Framework controls and leveraging some powerful native graphics features available in the Windows Mobile operating system."

Read it here...