Problems emerging cyrus-imapd

[villiam]

I am trying to emerge the cyrus imap dameon but the process has been failing at the same point during the configure script. The error I get is the following:

---- Error ------
checking for sasl/sasl.h... no
configure: error: Cannot continue without libsasl2.
Get it from ftp://ftp.andrew.cmu.edu/pub/cyrus-mail/.

!!! ERROR: The ebuild did not complete successfully.
!!! Function src_compile, Line 71, Exitcode 1
!!! bad ./configure
---- Error ------

Sasl 2.1.7 is installed (courtesy of emerge) in /usr (/usr/lib for the libraries and /usr/include/sasl for the header files)

The config.log file for cyrus-imapd (located at /var/tmp/portage/cyrus-imapd-2.1.5-r1/work/cyrus-imapd-2.1.5) contains the following information regarding the test for sasl

------config.log------
configure:5135: checking for sasl/sasl.h
configure:5145: gcc -E -I/usr/include/db3 -I/usr/local/include -I/usr/include -I$(srcdir)/../syslog -I/usr/lib/include conftest.c >/dev/null 2>conftest.out
------config.log------

I have tried manually running the configure script with:

configure --with-sasl=/usr/include/sasl/ as well as
configure --with-sasl=/usr/

with no success.

Any thoughts on what I can try next?