Accessing git.postgresql.org fails

This is ok:

git clone ssh://git(at)gitmaster(dot)postgresql(dot)org/postgresql.git

But this fails:
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$ git clone ssh://git(at)git(dot)postgresql(dot)org/postgresql.git
Cloning into 'postgresql'...
Permission denied on repository for user ishii
fatal: Could not read from remote repository.

Please make sure you have the correct access rights
and the repository exists.
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Is accessing git.postgresql.org wrong and should we access
gitmaster.postgresql.org instead?

Best reagards,
--
Tatsuo Ishii
SRA OSS, Inc. Japan
English: http://www.sraoss.co.jp/index_en.php
Japanese:http://www.sraoss.co.jp