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Description of problem:
The spec file for libungif sets an Obsoletes for giflib.
Since the Unisys patent has expired, some people may wish to install
the API compatable version of giflib and get lzw compression when
creating gif images.

When they do this, however, the obsoletes tag in libungif causes their
giflib to then be replaced by libungif again with a yum update.

The fix is simple, and should be considered for FC4 - remove the
obsoletes tag from the spec file, so that users who want to replace
libungif with a giflib package can do so without needing to set
excludes in their package update software.

Version-Release number of selected component (if applicable):
libungif-4.1.3-1

How reproducible:
Always

Steps to Reproduce:
1. uninstall libungif and replace with giflib that provides identical
files.
2. run yum update
3. yum will want to replace giflib with libungif
    

Additional info:

Workaround - tell yum/up2date/apt to ignore libungif if you want to
replace it with a giflib rpm.