Tru64 5.1B Patch Kit 5 installation fails

We have a server running Tru64 5.1B Patch Kit 4, and now that
Patch Kit 5 has been released I wanted to install it.
Unfortunately, an error while running dupatch occurs:

-------------------------------------------------------------------------

Problem installing:

  - Tru64_UNIX_V5.1B / Network Patches:
         Patch 26020.00 - SP05 OSFCLINET540 (SSRT3653 SSRT2384 SSRT2275 ...)
         ./sbin/init.d/snmpd:
                 its origin can not be identified.

This patch will not be installed.

-------------------------------------------------------------------------

    * The following 1 patch(es) failed in prerequisite/file 
applicability check:

Press RETURN to proceed...

  - Tru64_UNIX_V5.1B / Network Patches:
         Patch 26020.00 - SP05 OSFCLINET540 (SSRT3653 SSRT2384 SSRT2275 ...)

    * There were 1 patch(es) which failed in prerequisite/file 
applicability check:

Press <RETURN> to go back to the previous menu

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After that I can only go back to the main menu, so I can't
install anything at all :-(

I have no clue as to why dupatch doesn't recognize /sbin/init.d/snmpd.
However, we have the HP Insight Manager 3.3.0 and HP WEBES 4.4.0
services installed , so perhaps those may be related to the snmpd.

Does anyone know how to solve this error ?

Ole Holm Nielsen
Department of Physics, Technical University of Denmark