cfldap modify query to add members to group

Hi,

I am trying to add new members to the group using cfldap modify query.

i am able replace with one member with the other but the requirement is like that we supposed to add new member with the existing one.

query that i have used is

<cfldap

     ACTION="modify"

                      Modifytype="REPLACE"

                      DN="#groupdn#"

                      ATTRIBUTES="MEMBER=#existingmembers#, cn=XXX, ou=xxx,o=xxxx"

                      separator="|"

                      secure="#secure#"

                      server="#ldapServer#"

                      username="#ldapuser#"

                      password="#ldapPassword#"

                      port="#ldapPort#"

                     >

It is giving syntax violation error.

please help me get it resolved.

Thanks in advance.