LdapReadTimeout setting in oam-config.xml doesn't seem to work with OAM 11.1.2.2

We are in the process of upgrading from 10gSSO to OAM 11.1.2.2 for a number of our applications including eBusiness 12.1.3.  We have configured the Java External Authentication Plugin against an Active Directory farm that is managed by a 3rd party and on occasion the authentication can take 60 to 80 seconds.  This causes OAM to fail with the following error OAMSSA-20023 and  LDAP Error 1 : LDAP response read timed out, timeout used:30000ms. with primary error message {3}.  The login screen then tells the user that they have entered an incorrect userid or password.  I've enabled debugging for the