Upgrading to net/openldap22-sasl-server giving fits

My 5.2-CURRENT server is happily chugging away using openldap21-sasl-server 
with the db41 backend, nss_ldap, and pam_ldap for user authentication.  
After reading in /usr/ports/UPDATING that openldap22-(sasl-)?server was 
becoming the default I thought I'd try upgrading to it.

Unfortunately, upgrading to openldap22 with db41 results in:

bdb_initialize: initialize BDB backend
bdb_initialize: Sleepycat Software: Berkeley DB 4.1.25: (December 19, 2002)
>>> dnNormalize: <cn=Subschema>
=> ldap_bv2dn(cn=Subschema,0)
<= ldap_bv2dn(cn=Subschema,0)=0
=> ldap_dn2bv(272)
<= ldap_dn2bv(cn=subschema,272)=0
<<< dnNormalize: <cn=subschema>
>>> dnNormalize: <>
<<< dnNormalize: <>
Unrecognized database type (bdb)
database bdb initialization failed.
slapd shutdown: freeing system resources.
slapd stopped.
connections_destroy: nothing to destroy.

...and upgrading from db41 to db42 results in an unreadable database.  Has 
anyone successfully moved from OpenLDAP 2.1 to 2.2? 
-- 
Kirk Strauser