Here are instructions for how to resolve the issue where you encounter this error:
/usr/include/gpgme.h:80:2: error: #error GPGME was compiled with _FILE_OFFSET_BITS = 64, please see the section "Largefile support (LFS)" in the GPGME manual.
This is a result of the gnupg extension currently lacking largefile support. The solution is fairly simple.
pecl download gnupg
tar -zxf gnupg-1.3.2.tgz
Open the file config.m4 in an editor, and add "AC_SYS_LARGEFILE" to a new line at the very end of the file, then save.
Now simply add extension=gnupg.so to your php.ini, and the extension should work.