Case sensitivity/caching issue for autoloaded parent classes

when class extends parent class,but code parent class differences class real name(lowercase class name is same),this problem appears in web mode.
first access hhvm no problem,but seconde access (beacause first access class have cached),and throw fatal:
error 1:
HipHop Fatal error: File not found: /mnt/huzhiguang/data/hhvm/class/autoload/TeSt_Base.php in /mnt/huzhiguang/data/hhvm/class/autoload/test1.php on line 5

error 2:

[Tue Jul  1 14:25:43 2014] [hphp] [28065:7f868e9ff700:12:000001] HipHop Fatal error: unknown class Opsystem_Base in /home/work/orp001/app/testapp/actions/A1.php on lin
e 8

replay problem issuse:
https://github.com/facebook/hhvm/issues/3146
It's a tradeoff between stability and keeping the code maintainable. Keeping old code around 'just in case' leads to more problems in the long run - especially as we have fairly comprehensive automated test case. Please modify this PR to only do the one case unless you know of a way that it's incompatible, in which case, please share an example.