brakes lost, 86 coupe GT

["kevin kraus" <kevinkraus@usa.net>]

Over a month ago I suddenly lost my brakes.
I went to my local shop and they installed a new right brake line.
Last week they went out again,
Upon taking it back to the shop,
the mechanic said that the parking brake cable had
rusted and that it was causing the leak to the right rear.
They replaced the cable.
Now today the brakes have gone again.
Back to the shop tomorrow morning.

Does anyone have an idea on what is happening?

thanks,

Kevin