[Dovecot] Dovecot 2.2.0 Compilation Error

On MacOSX 10.6, I get:

ld: duplicate symbol _cmd_batch in dsync/.libs/libdsync.a(doveadm-dsync.o) and doveadm-mail-batch.o for architecture x86_64 collect2: ld returned 1 exit status make[4]: *** [doveadm] Error 1

when compiling Dovecot 2.2.0. By contrast, 2.1.16 compiled (and runs) just fine.

I'm surprised that this hasn't cropped up elsewhere.