Form Header not working when form opened in frameset

I have a form on which I’m utilizing a form header so that the information at the top remains visible when the user scrolls. On the form I also have an embedded single category view of documents related to the main form. The header works fine until I open the form in the top of a two frame frameset. Documents selected in the embedded view are opened in the bottom frame. I used Target Frame(single click) in the embedded view to target the lower frame. All of this works great except for the fact that now that the parent doc form is opened in the frameset the header no longer remains stationery. The form acts as though there is no header defined and that area scrolls along with the rest of the form.

I know there is a known issue with a table being the first element in the header and this is not the case on my form. There is a single row table in the header but there are other fields above it. As I mentioned, the header works fine as long as I open it outside of the context of the frame.

Is there some trick to make this work?