Duplication of 'You must enter a message when posting' error

[r1Pped]

What i am looking to try and do is duplicate the error you recieve when you dont enter a subject heading for another text entry form.

What i have used is based on the Ctracker submission form and would like that all the text entry boxes must be filled before being allowed to post.

Forums are found [url=http]here[/url] and the particular topic submission form can be found [url=http]here[/url].

Its the the other text entry boxes i have that i am looking the error to appear on.

Anyone have a graps of what i am trying to get at and can help?