>
> Using what libcurl version?
>
> No, a reverse lookup is never needed by libcurl but in the past some were
> accidentally performed.
>
> --
> Commercial curl and libcurl Technical Support: http://haxx.se/curl.html
>

I´m using an older version (7.12.0 with c-ares 1.2).
I used 'netstat' to ensure, that the HTTP-Client is the one doing the
lookups. Other executables I created using libcurl, do not do any lookups on
the same machine, connecting to the same proxy.
I turned on the CURLOPT_VERBOSE in the HTTP-Client to get more information
and...there are no lookups anymore???

I think 'accidently performed' is right, I´ll try a newer version of
libcurl.

Thanks,

Joachim

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