Although too late, I second the Flush Cut saw. Grab one at Harbor Freight if you can. They are really cool.
Its amazing how sharp they are, and they cut really fast with minimal effort.
The blades so thin, theres very little resistance from the material.. and the teeth are razor sharp.. and surprisingly, out of all the cuts Ive made, they still are sharp as hell.
Its nice to for small cut jobs, or specialty situations, like what you ran into. (which is their intended purpose)