[Maria-developers] Why local modifications to PCRE library?

Alexander, I see you've included the full source of PCRE library into MariaDB tree and even made some local modifications which are not included into PCRE upstream. Could you please explain why did you do that? Why not allow to build with system standard PCRE library? I understand that you could have needed some modifications and thus could want to include sources from PCRE trunk to allow users to build with modifications when their system-wide library is too old. But as I don't see your modifications on PCRE trunk that means you probably had something different in mind, and decided to incur the pain of constantly updating the included sources and merging security fixes. So why did you decide to do that? Thank you, Pavel