Commercial windows - Leak repair in Dallas, TX

All,

I have a townhouse property with large commercial style windows on the front (Think 18ft H x 12ft W). These are large aluminum frames, like you'd find in store fronts. I don't have a pic, but here's an example:

http://media-cache-ec0.pinimg.com/736x/7b/e5/03/7b...

The problem is that when it rains, the windows leak from the bottom of the frames into the house. It's not a rapid flood, just enough to get the window sill damp.

I'm having a hard time finding qualified window companies to work on them. All the companies I've dealt with in the past are good with residential style windows, but when I tell them about these, the say they don't have any experience with them. I've tried 5 already, so I decided to try my luck here.

Does anyone have a good commercial style/store front window glass companies they deal with in Dallas/Ft Worth area?

Thanks,

Fouad