Yes I'm running 4 virtual applinces in all: VMware vCenter Server Appliance 5.1, vSphere Data Protection, vSphere Replication Appliance nad Dell_VC_Pluggin.i686-1.5.1.
New exploring - I'm able to ping W2008 VM from VCSA and opposite way but tasks still stay queued in Recent Tasks panel in web client. It turns to errors immediately if I run "Windows" vSphere Client. Next check pass well.