On Wed, 24 Oct 2007, Song Ma wrote:

> Looks like this does not directly related with OpenSSL neither. I tried
> connection from two machines. One is UNIX and the other is Linux. The curl
> version is different (7.16.1 and 7.17.1 dev version) and the OpenSSL version
> is also different (0.9.7d and 0.9.8f). But the result is same: if you invoke
> several connections within a short time, a few will be success and the other
> will fail anyway.
>
> Looks like the website has some protection mechanism to not accept every
> connection request.

This was also the conclusion on the openssl list where Jake took this issue:

http://thread.gmane.org/gmane.comp.encryption.openssl.user/28004/focus=28005

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