warning: guix collision encountered

[Cook, Malcolm]

Hi,

In https://gnunet.org/bot/log/guix/2014-12-08 I read

        I just installed my second binary package (emacs) and I get this 
warning:
        [19:33:50]      <rekado>        warning: collision encountered: 
/gnu/store/wsa1hpnqa9rzpw3irkr03ad6q3xblpmj-info-dir

I too am getting collisions, for me while installing 'socat' , and especially 
oddly between dconf and emacs

I don't see any mention of collisions in  
http://www.gnu.org/software/guix/manual/guix.html and am at somewhat of a loss 
to grok the output of the report:

Any guidance appreciated.  

Trace follows:

bash-4.2$ guix package -i socat
warning: failed to install locale: Invalid argument
The following package will be installed:
   socat        1.7.2.4 
/gnu/store/0w2fcwdvkss8n6hgj7a8bgybjx2qwhi5-socat-1.7.2.4

substitute: warning: failed to install locale: Invalid argument
updating list of substitutes from 'http://hydra.gnu.org'... 100.0%g'...  83.3%
The following derivations will be built:
   /gnu/store/gya4c2c1pzxhr65p2z4gaw73cjpyby7c-profile.drv
   /gnu/store/lmzj4f36ngdnfmfh784maf7mvyp0pspr-info-dir.drv
   /gnu/store/q879rs72krrihxgv6blyq07zd4dv8zy0-ca-certificate-bundle.drv
   /gnu/store/rs3n7s0bv1if21pjd8x72zqaqcbfs5h6-gtk-icon-themes.drv
The following file will be downloaded:
   /gnu/store/0w2fcwdvkss8n6hgj7a8bgybjx2qwhi5-socat-1.7.2.4
warning: failed to install locale: Invalid argument
found valid signature for 
'/gnu/store/0w2fcwdvkss8n6hgj7a8bgybjx2qwhi5-socat-1.7.2.4', from 
'http://hydra.gnu.org/nar/0w2fcwdvkss8n6hgj7a8bgybjx2qwhi5-socat-1.7.2.4'
downloading `/gnu/store/0w2fcwdvkss8n6hgj7a8bgybjx2qwhi5-socat-1.7.2.4' (0.5 
MiB installed)...
http://hydra.gnu.org/nar/0w2fcwdvkss8n6hgj7a8bgybjx2qwhi5-socat-1.7.2.4  192.2 
KiB transferred (579. KiB/s)
warning: collision encountered: 
/gnu/store/4zmkk7mwn4v2iid4nqldlxx9g6nszc5l-dconf-0.22.0/share/icons/hicolor/icon-theme.cache
 
/gnu/store/1qrbdgrk7p6c1z80kz49gj6gsfk444wf-emacs-24.5/share/icons/hicolor/icon-theme.cache
 
warning: arbitrarily choosing 
/gnu/store/4zmkk7mwn4v2iid4nqldlxx9g6nszc5l-dconf-0.22.0/share/icons/hicolor/icon-theme.cache