Add message in first post

[redfinite]

I was hoping someone could help me with a simple mod. I would like to add a small .png graphic to the end of the first post of a thread. I dont want this repeated for the every post the threadstarter makes after this, just the original post.

The small catch is I would also like to be able to limit this feature to select forum ID's also.

I have searched but while there are a few mods based around this most highlighted the threadstarter for the whole thread and couldn't be limited to certain forums. Im hoping its just a matter of adding some code to the templates.

Thank you very much.