mnt-lower attribute not allowed?

 Dear colleagues,

 yesterday I tried to apply the hierarchical authorisation scheme on
 route objects. However, I did not succeed. As an example, have a look
 at this:

route:       193.174.0.0/15
descr:       DFN-AGG-1
origin:      AS1275
mnt-by:      DFN-MNT
mnt-lower:   DFN-MNT
changed:     poldi at dfn.de 950907
changed:     noc at noc.dfn.de 961001
source:      RIPE
password:    ...

 resulted in:

Update FAILED: [route] 193.174.0.0/15
 
route:       193.174.0.0/15
descr:       DFN-AGG-1
origin:      AS1275
mnt-by:      DFN-MNT
changed:     poldi at dfn.de 950907
changed:     noc at noc.dfn.de 961001
source:      RIPE
*ERROR*:     attribute "mnt-lower" unknown in route object

 Is this just an error in typing (I took the same spelling as given in
 the RIPE database 2.0 workshop), or is hierarchical authorisation not
 done for route objects (in the workshop there was only an example for
 inetnum objects), or is it just not implemented yet?
 If it was implemented only for inetnum objects I do not see any reason
 why it should not be also possible for route objects.
 Could anybody please give a hint?

 Regards
    Joachim
_____________________________________________________________________________

 DFN Network Operation Center, Dr. Joachim Schmitz, (finger help at noc.dfn.de)
                     >>>>>> mailto:  noc at noc.dfn.de   <<<<<<
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