# diff -u  /usr/bin/pt-show-grants.orig /usr/bin/pt-show-grants 
--- /usr/bin/pt-show-grants.orig        2012-03-05 11:05:36.065012509 -0800
+++ /usr/bin/pt-show-grants     2012-03-05 11:00:19.266887251 -0800
@@ -1744,7 +1744,7 @@
             my $grant = $_;
             PTDEBUG && _d($grant);
             my ( $grants, $on_what, $user ) = $grant
-               =~ m/GRANT (.*?) ON ((?:`|\*).*?) TO ('[^']*'\@'[^']+')?/;
+               =~ m/GRANT (.*?) ON ((?:`|\*|').*?) TO ('[^']*'\@'[^']+')?/;
             PTDEBUG && _d('grants:', $grants, 'on_what:', $on_what,
                'user:', $user);