I came across an issue in MOSS 2007 with the site collection backup and restoration. This has come up along with SP2.
When we had gone for a backup of the site collection we went ahead with the default parameter stsadm -o backup -url http://server_name/sites/site_name -filename site_name.bak
and then we restored it using the stsadm command
stsadm -o restore -url http://server_name/sites/site_name -filename site_name.bak
Once restored we faced a funny issue in which we were not able to delete Site Collection Administrators nor we were able to edit the pages.
We did our analysis and found out that when we had done a backup withe the above STSADM command, we had missed out another parameter -nositelock . This locked the site collection when the backup was done. Once restored, the lock on the site collection still persisted. We had to go Central administration page --> Application Management --> Site collection Quotas and locks link. There we have the option to remove the read only option. Once we remove the read only permission, we were able to do all site administration tasks on the site collection.
Hope this helps..
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