Turn off closing tag automation in src

Hi all!

I have some trouble with some functionality that automatically closes tags I write in the source mode of the FCKEditor. I do have some obscure extra tags, and FCKEditor automatically closes them in a way that breaks their functionality.

If I for example write

<MY_CUSTOM_TAG/>

in the source mode, FCKEditor transforms it to

<my_custom_tag></my_custom_tag>

I have found a way to prevent the FCKEditor from the lowercase-operation, but I can't seem to prevent it from transforming my single tag to a pair.

Do anyone have an idea as of where I should look, or if there are any configuration parameters I could use?

Thanks!

Andreas