Regarding to the scan listener is the relocation not being handled correctly by Oracle Enterprise Manager(OEM) 11gR1 (shows target as down after relocate!), Oracle has solved this by the following bugs/fixes:
Apply Patch 10118817 on OMS: BUG 10118817 - SCAN LISTENERS NOT BEING DISPLAYED CORRECTLY IN GC CONSOLE AFTER FAILOVER
(this is a generic platform fix)
Apply Patch 10392806 on AGENT: Bug 10392806: METADATA CHANGES FOR BUG 10118817
(this patch is available on linux x86/x86-64)
Usually after these patches, the fix should work, if all the post install steps, agent patches are applied correctly.
There is one more scenario in the bug 10118817 where in the cluster target metrics in EM "crs_event" and "resource_status" are present in $AGENT_HOME/<host>/sysman/emd/collection/cluster_<ClusterName>.xml. You will have to remove these metrics, as mentioned in the bug.
Keep in mind those patches are conflicing with the PSU 2 patch. There is a request by Oracle to solve this also for the PSU patch 2.If installed the PSU 2 patch you can not use this patch .