Tool Window

What is the best way to create a tool window in MDI application? I have created a regular window and made it a child of parent MDI window and made it topmost window. It works fine, but the only problem is that when I select other child window (other document or other tool window), the title bar area turns to inactive color. It behaves fine, but it just doesn't look right. Is there a way to make a window always have active title bar? Thanks.