[exim] IPV6 error in exim, though disable_ipv6=true

Hello,

I am trying to set up exim4 to use my gmail account. But mail is queued
and is never sent because the log says:

2014-04-10 22:48:05 Start queue run: pid=12623 -qff
2014-04-10 22:48:05 1WYK8P-0001YZ-Ix IPv6 socket creation failed:
Address family not supported by protocol
2014-04-10 22:48:05 1WYK8P-0001YZ-Ix gmail-smtp-msa.l.google.com
[2a00:1450:400c:c03::6c] Address family not supported by protocol

I have Exim 4.80 with support for
crypteq iconv() IPv6 GnuTLS move_frozen_messages DKIM

In /etc/exim4/update-exim4.conf.conf, I have at the end:

disable_ipv6='true'
dns_ipv4_lookup='*'

I have reloaded my configuration and restarted exim4:
# update-exim4.conf
# service exim4 restart

Restarts fine, but mail gets queued, and telling it to process the queue:
# exim -qff

results in that log error in /var/log/exim4/mainlog.

Can somebody help me out ?

Thanks!

PS. If that helps, I'm on a Raspberry Pi, Raspbian.