Problems trying to minimising application

We have created a MDI application and we have just realised that the
application will not minimise will it is running. When the minimise button
is pressed it seems to send the application to back.

We have been tearing our hair out a while now, but we have no idea what we
have done wrong.

The application will however maximise and we can change the size of the main
form. There are no constraints on the form and it the AutoSize property is
not FALSE.

The minimise was working up until about a month ago; we have backtracked our
code and cannot find any problems. We are not sure if the problem will be in
the .pas file or the .dfm.

Any help or suggestions would be much appreciated.

Neil Dosdale.