cubicweb #706958 Error when doing a pg_dump [deprecated]

On a dump I get

error while calling sys_path_init for posgtgres plpython initialization: function sys_path_init(unknown, unknown) does not exist
LINE 1: SELECT sys_path_init(E'/home/arthur/etc/cubicweb.d/sysinfo||...
HINT:  No function matches the given name and argument types. You might need to add explicit type casts.

yet postgres-plpython-8.4 is installed...

done in<not specified>
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