compile warning msg

[Norman Zhang]

When I compile cyrus-imapd-2.0.13, with
./configure --with-auth=unix --with-dblib=/usr/lib/ --with-sasl=/usr/lib/
How can I get ride of the warning message?

configure: warning: Parts of com_err distribution were found, but not
compile_et.
configure: warning: Will build com_err from included sources.

I copied the com_err.h from /tmp/cyrus_imapd-2.0.13/et/ to /usr/include/.
Appreciate if anyone can give some pointers.

Thanks and Regards,
Norman