Error on initdb with 7.4RC2

When running initdb on a fresh 7.4 install I get this error:

postgres(at)bugs:~$ /usr/local/pgsql/bin/initdb -D /usr/local/pgsql/data -E
latin1
The files belonging to this database system will be owned by user "postgres".
This user must also own the server process.

The database cluster will be initialized with locale es_AR.

creating directory /usr/local/pgsql/data... ok
creating directory /usr/local/pgsql/data/base... ok
creating directory /usr/local/pgsql/data/global... ok
creating directory /usr/local/pgsql/data/pg_xlog... ok
creating directory /usr/local/pgsql/data/pg_clog... ok
selecting default max_connections... 10
selecting default shared_buffers... 50
creating configuration files... ok
creating template1 database in /usr/local/pgsql/data/base/1... FATAL:
semctl(1638435, 16, SETVAL, 536) failed: Argumento inválido

Any ideas on how to fix it?

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Martín Marqués | select 'mmarques' || '@' || 'unl.edu.ar'
Centro de Telematica | DBA, Programador, Administrador
Universidad Nacional
del Litoral
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