exclude a pattern but only in the top level

[Brian K. White]

Consider the following directory structure

/foo/aaa/*/*
/foo/bbb/*/*
/foo/ccc/*/*

I want to sync all of /foo,
but exclude /foo/aaa
but not exclude any other occurances of "aaa" or "foo/aaa" (be they 
files or dirs) that might occur within the other dirs /foo/bbb/* 
/foo/ccc/* etc

I don't want to exclude /foo/bbb/aaa or /foo/ccc/111/aaa or 
/foo/ccc/111/foo/aaa etc...

Destination is running rsync daemon and has a module named root that 
points to "/" such that normally, for the full /foo with no exclude, 
it's very simple, my rsync command would just be:

rsync -avz /foo ${DEST}::root

That works fine without the exclude.

So, to that I want to add a filter file. (Well, I assume that's what I want)

rsync -avz -f ". filter" /foo ${DEST}::root

If I construct a filter file like this:
- aaa
+ *

or like this
- aaa/
+ *

or like this
- foo/aaa/
+ *

rsync hides the top level /foo/aaa but it also hides any other 
occurrences of the exclude pattern that occur anywhere within the job 
instead of just the top level one.

How can I get it to exclude just the top-level directory "/foo/aaa" ?

-- 
bkw