Permissions problems in /usr/share/mime cause icons to disappear

[Filipe Bonjour]

Hi,

I'd like to report a problem that I had several times when I was running 
Fedora, and I just had it again for the first time with Ubuntu (5.10). 
As I know how to work around it, this is mostly a curiosity...

I use QuickLounge to hold a bunch of launchers on my Gnome Panel. Every 
now and then, the launchers icons simply disappear from the applet. The 
second or third time I got it with Fedora, I decided to investigate and 
noticed that some icons wouldn't work with Nautilus either. So I 
launched Nautilus with strace and discovered that it was unable to read 
files from /usr/share/mime. I logged in as root, ran "find 
/usr/share/mime -type f -exec chmod o+r {} \;" and everything was OK 
again. I could never determine what caused the problem.

The only two things that I can see I did yesterday that could have 
caused the problem today were:

* I deleted by mistake my Nautilus link to "Home" on the desktop (d'oh!).
  I doubt this is the cause, as my normal user shouldn't have access to
  /usr/share/mime;
* I installed a trial version of VMWare 5.5;
* I used Synaptic for the following modifications:
    => Installed gcc-3.4-base, cpp-3.4, gcc-3.4, linux-headers-2.6.12-10,
       linux-headers-2.6.12-10-686 to compile the VMWare kernel modules.
    => I also had some trouble finding the package with the kernel modules
       (which were in linux-headers-*), so I installed then uninstalled
       linux-kernel-headers.
* And, yes, I installed a new VM in VMWare. As this was done as root,
  it's conceivable that I broke something...

Could any of this have caused the problem? Has anyone seen this?

Thanks,

Filipe

-- 
Filipe Bonjour

      In theory there is no difference between theory and practice.
      In practice there is. -- Yogi Berra