force change of package version

[Chris Jones]

Hi,

How can I force change the vesion of a package using yum ?

I am trying to install some packages on a Fc4 system I upgraded from 
FC3, but get the following error

yelp-2.10.0-1.i386.rpm    100% |=========================|  21 kB    00:00
---> Package yelp.i386 0:2.10.0-1 set to be updated
--> Running transaction check
--> Processing Dependency: libxpcom.so for package: yelp
--> Processing Dependency: libgtkembedmoz.so for package: yelp
--> Processing Dependency: mozilla >= 1.7.8 for package: yelp
--> Restarting Dependency Resolution with new changes.
--> Populating transaction set with selected packages. Please wait.
---> Package mozilla.i386 37:1.7.8-2 set to be updated
--> Running transaction check
--> Processing Dependency: mozilla-nss = 37:1.7.8-2 for package: mozilla
--> Processing Dependency: mozilla-nspr = 37:1.7.8-2 for package: mozilla
--> Finished Dependency Resolution
Error: Missing Dependency: mozilla-nss = 37:1.7.8-2 is needed by package 
mozilla
Error: Missing Dependency: mozilla-nspr = 37:1.7.8-2 is needed by 
package mozilla

and

root at localhost /home/jonesc > rpmquery mozilla-nss mozilla-nspr
mozilla-nss-1.7.8-2.0.fc3.kde
mozilla-nspr-1.7.8-2.0.fc3.kde

So it seems I have a few old FC3 pacakges left over causing problems. 
How can I switch over to the FC4 versions ? If I try a yum remove on the 
above packages, then many many other packages are also tagged for 
removal which I don't want.

Note, with apt and syanptic I would just do a "force version" to fix 
this - Is thre something similar for yum ?

Chris


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