Newbie question

Hi all !

I'm new to this mailing list and I need some help
when using the BTemplate component with tables:

I have a table where some of the rows - not following a certain pattern -
need to have
a different color that the others depending on a certain condition.
So I added a directive - Dir::Get_Data.SomeModel.row - to the <tr> element
together
with the Iterate_Start and Iterate_Next directives,
so that I can define a bgcolor attribute when needed.
But what do I need to return in my Model (which implements IterativeModel)
in getItem(key) for the row directive ?
I'd like to maintain the <tr> element as it is defined in my HTML file
and just add a bgcolor="..." attribute to it depending on a certain
condition.

Any help is highly appreciated.
Thanks and greets,

Thorsten