1) is your vMotion network a private physical switch/VLAN only used by ESX servers, or is this on a public network.
2) Are you routing the vMotion between two networks.
3) Please post output of:
esxcfg-vmknics -l
esxcfg-route -l
esxcfg-nics -l
vmkping vMotionIPofTargetHost
4) review /var/log/vmkernel for any errors regarding the vMotion.
Check this links also:
http://communities.vmware.com/message/445938#445938
http://communities.vmware.com/thread/117805?tstart=0
http://communities.vmware.com/message/467069#467069
http://blog.scottlowe.org/tag/cisco/
