Spring Security LDAP Configuration BeanCreationException on app server startup
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I'm trying to hook up my Spring 3.1 app to my in-house Zimbra LDAP server.  I'm doing something likely very stupid and I cannot see the problem.  I'm certain there could be issues with the group and user base and filter terms I defined, but that shouldn't be causing a BeanCreationException on app server startup, should it?  I could use another pair of eyes...

The short version of the exception:

"Can't convert an LdapAuthenticationProvider to required type AuthenticationProvider for property providers[0]"

The full exception:

    org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'org.springframework.security.authentication.ProviderManager#0': Cannot create inner bean '(inner bean)' of type [org.springframework.security.config.authentication.AuthenticationManagerFactoryBean] while setting bean property 'parent'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name '(inner bean)#16': FactoryBean threw exception on object creation; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'org.springframework.security.authenticationManager': Initialization of bean failed; nested exception is org.springframework.beans.ConversionNotSupportedException: Failed to convert property value of type 'java.util.ArrayList' to required type 'java.util.List' for property 'providers'; nested exception is java.lang.IllegalStateException: Cannot convert value of type [org.springframework.security.ldap.authentication.LdapAuthenticationProvider] to required type [org.springframework.security.authentication.AuthenticationProvider] for property 'providers[0]': no matching editors or conversion strategy found



The relevant Spring configuration file entry:

    <security:authentication-manager>
        <security:ldap-authentication-provider
            group-search-filter="member={0}"
            group-search-base="ou=groups"
            user-search-base="ou=people"
            user-search-filter="uid={0}"
        />        
    </security:authentication-manager>
 	
 	<security:ldap-server url="ldap://<correct IP and port>" manager-dn="uid=zimbra,cn=admins,cn=zimbra" manager-password="<private>" />


Thanks for any insights you can provide!  