I'm not sure this is a bug, but I'll try to explain what I found.

I have program written in PHP (using php-mode) and when ever I'm over the 
1000 lines inside an open {, the closing } doesn't show where the block 
started. If I'm within the 1000 lines (block has less then 1000 lines) it 
shows in the minibuffer where the block started.

versions:

$ dpkg -l | grep -i emacs
ii  emacs21                       21.4a-3               The GNU Emacs 
editor
ii  emacs21-bin-common            21.4a-3               The GNU Emacs 
editor's shared, architecture
ii  emacs21-common                21.4a-3               The GNU Emacs 
editor's shared, architecture
ii  emacsen-common                1.4.17                Common facilities 
for all emacsen
ii  php-elisp                     1.1.0-2               Emacs support for 
php files


I hope I was clear. If you need any debugging, feel free to ask.

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