no primary key on self designed type

Hello,

create type inrecord (
    internallength=VARIABLE,
    input=inr_in,
    output=inr_out
);

create table test (
    data    inrecord not null primary key
);
... result ...
ERROR:  Can't find a default operator class for type 268128.

how can I define the default operator class ??
--
mit freundlichem Gruss -- regards
        ,-,
       |  |         Thomas Drillich <drillich@uniserve.de>
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