[Dovecot] error in config file?

When I start dovecot I am getting an error about the ocnfig file.

watson:~# /etc/init.d/dovecot start Starting mail server: dovecotFatal: Error in configuration file /etc/dovecot.conf line 185: Missing value

So I look int /etc/dovecot.conf and line 185 is

mbox:~/mail/:INBOX=/var/mail/%u/

Which seems like valid syntax according to the docs. I am using dovecot 0.99.10-2