Modifying users password in pg_shadow from php

Hi All,
I'm wonder if there is any possibility to modify a users password by
updating the pg_shadow table.
I'd like to ensure that when the user modifies his/her http password
(htpasswd) than his database password also changes. It is important to have
the same password for both services. I plan to do it from php.

Is there any way to do so?

Thans,
-- Csaba Együd

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