sha1 function

We are at the moment planning on passing some passwords that are plain
texted in our DB to some encrypted form as now they will be used for
processes that require better security measures.

We started looking at md5() but found that it's easy to crack and one of
the systems uses CHAP authentication, and so SHA1 hashing.

So, two questions arise.

1) Is MD5's weakness true?

2) Is there any sha1() functions in PostgreSQL?

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Lic. Martín Marqués | SELECT 'mmarques' ||
Centro de Telemática | '@' || 'unl.edu.ar';
Universidad Nacional | DBA, Programador,
del Litoral | Administrador
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