Recommended way to modify cn=schema entries?

[Ian Collins <ian@ianshome.com>]

I would like to re-order two schema entries to resolve a dependency 
issue (our local schema, included before dyngroup.schema, now references 
memberURL).

However deleting a schema entry with ldapmodify does not appear to be 
supported:

dn: cn={8}dyngroup,cn=schema,cn=config
changetype: delete

deleting entry "cn={8}dyngroup,cn=schema,cn=config"
ldap_delete: Server is unwilling to perform (53)

Any suggestions?

--
Ian.