The function lib/hostip.c:Curl_getaddrinfo() which does the resolve in this case attempts to see if IPv6 "works" or not and if it doesn't work it uses PF_INET and otherwise it uses PF_UNSPEC.

It sounds to me like either that check doesn't work, or you haven't "truly" disabled IPv6...

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** [bugs:#1274] IPv6 DNS requests were sent out from Android Handsets even if the IPv6 stack is not present on the device.**
**Status:** open
**Labels:** Android-IPv6 Issue 
**Created:** Tue Sep 03, 2013 09:36 PM UTC by Rajiv Dwivedi
**Last Updated:** Wed Sep 04, 2013 09:34 PM UTC
**Owner:** Daniel Stenberg
Observation:
IPv6 DNS requests were sent out from Android Handsets even if the IPv6 stack is not present on the device.
Expected Result:
If there is no IPv6 stack on the device/machine, the IPv6 request should not be sent from the device.
Workaround:
Using option "CURL_IPRESOLVE_V4", disables sending IPv6 DNS queries.
Libcurl details:
OS: Linux - Android
version: 7.32.0
link: http://curl.haxx.se/download.html
Attachments:
Wireshark log ( which displays both Ipv$ and IPv6 records)
Verbose output using libcurl (captured while making HTTP requests)
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