package indicator-weather 11.04.10 repack-0ubuntu2 failed to install/upgrade: subprocess installed post-installation script returned error exit status 127

Confirmed. See Bug #804103

Setting up indicator-weather (11.04.10+repack-0ubuntu2) ...
/var/lib/dpkg/info/indicator-weather.postinst: 23: gtk-update-icon-cache: not found
dpkg: error processing indicator-weather (--configure):
 subprocess installed post-installation script returned error exit status 127

It seems that we need an explicit dependency on libgtk2.0-bin in oneric.

This bug was fixed in the package indicator-weather - 11.05.31-0ubuntu1

---------------
indicator-weather (11.05.31-0ubuntu1) oneiric; urgency=low

  * New upstream release.
   - Ported settings to dconf, which will solve a number of
     desktopcouch-related bugs
   - Fix for LP: #747733 "indicator-weather crashed with
     TypeError in next_page(): unknown type (null)"
   - Fix for LP: #756704 "Numbers (temperature etc.) do
     not use local number format"
   - Fix for LP: #770652 "sunrise and sunset info incorrect"
   - Fix for LP: #765464 "do not see indicator-weather on the panel"
   - Fix for LP: #769842 "Weather Indicator should clear up corrupted DB"
   - Fix for LP: #778941 "Weather Indicator can't be disabled"
   - Fix for LP: #796314 "ROUND_CEiLiNG error in Turkish locale"
   - Fix for LP: #780973 "indicator-weather crashed with Unauthorized in
     request(): ('unauthorized', 'Authentication required.')"
  * debian/control:
   - Adjust dependencies for desktop-couch to dconf transition.
   - Bump Standards-Version to 3.9.2.
   - Explictily depend on libgtk2.0-bin to ensure we have
     /usr/bin/gtk-update-icon-cache (LP: #808387).
  * Convert from python-support to dh_python2.
  * debian/rules:
   - Drop get-orig-source target, not needed.
   - Fix debian/postinst to check for symbolic links as well.
 -- Andrew Starr-Bochicchio <email address hidden> Tue, 12 Jul 2011 01:44:53 -0400

This is obviously not actually fixed. It is in fact a bug in gtk+2.0, which doesn't ship the /usr/bin/gtk-update-icon-cache symlink on architectures other than i386. See bug #810747