If you ever have the need to generate an encrypted password to put it into scripts or anything else, then you can use the following SQL command to generate it:
Important is, that your rolename is appended to your password and this construct then put into md5. The important piece in the source is [pg_md5_encrypt()](http://git.postgresql.org/gitweb/?p=postgresql.git;a=blob;f=src/backend/libpq/md5.c)