http://www.pix8.net/pro/pic/67649miEK/214115.jpg
As you can see i the picture above, or http://www.pix8.net/pro/pic/67649miEK/214115.jpg if you can't, i just made a hole in my application.

It's a timer I use to keep track of hours spent in a project.
I added a textbox to specify usage and to my surprise it turned out, not only transparent but _hollow_.
If I click in the textbox, focus is shifted to the application underneath, same thing for the X in the close button in upper right corner, however clicking on the red area works.
I used Dn'D in VS 2003, all properties are at default except MaxLenght which is set at 32.
That is the only change I have made to the application, I have never seen this behaviour before
How do I get it back to normal?

tnx Anders