>>> glob.glob('*.{sub,ac}')
['config.sub']

I'm surprised this broke, this is one of the behaviour I thought I had implemented in my original patch. :-/

> (and moreover, now it is impossible to glob for paths that contain braces)

I am absolutely sure this was working in my original submission, I had even added unit tests for it:
+        # test some edge cases where braces must not be expanded
+        eq(self.glob('c{}d'), [self.norm('c{}d')])
+        eq(self.glob('c{d{e,f}g'), map(self.norm, ['c{deg', 'c{dfg']))
+        eq(self.glob('c{d,e}{f}g'), map(self.norm, ['cd{f}g', 'ce{f}g']))
+        eq(self.glob('c{d,e}f}g'), map(self.norm, ['cdf}g', 'cef}g']))