Description of problem:
A command like this:

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mount -vv -t iso9660 -o loop,ro,fscontext=system_u:object_r:public_content_t:s0
/var/distro/FC-6-i386-disc1.iso /var/distro/mnt/1
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Fails with:

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mount: translated fscontext 'system_u:object_r:public_content_t:s0' to
'system_u:object_r:public_content_t:s0'
mount: going to use the loop device /dev/loop0
set_loop(/dev/loop0,/var/distro/FC-6-i386-disc1.iso,0): success
mount: setup loop device successfully
del_loop(/dev/loop0): success
mount: wrong fs type, bad option, bad superblock on /dev/loop0,
       missing codepage or other error
       In some cases useful info is found in syslog - try
       dmesg | tail  or so
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The same used to work just a week ago or so. Since then, there has been an
update to selinux-policy, but I'm not sure if that's somehow related. Anyway,
the version of the policy is 2.4.3-10.fc6.

Version-Release number of selected component (if applicable):
2.13-0.45.fc6

How reproducible:
Always.


Steps to Reproduce:
1. Attempt to mount an ISO filesystem while with fscontext or context option.

  
Actual results:
Mount fails.

Expected results:
Should work.

Additional info:
This is a mount done by hand. SELinux is running in targeted mode.