RHEV Admin Portal presents "Empty" as a vnic profile on VM Edit dialogue

Issue

There are two problem related to VM's nic profile:
1) On the database, as well as on the sub-form of the VM the nic presented ok, with the correct profile set. But when opening the VM Edit dialogue - the field shows "Empty" value. If open the combo-box - available profiles are listed correctly.
2) Updating the profile via that interface fails. No error is reported to the user, but the result is same - the dialogue shows "Empty" as vnic profile.
In the engine.log you can see this flow:

2014-06-06 17:18:19,110 INFO  [org.ovirt.engine.core.bll.UpdateVmCommand] (ajp-/127.0.0.1:8702-48) [4861a0b5] Running command: UpdateVmCommand internal: false. Entities affected :  ID: 0c6ff3d3-8d8e-495f-84ce-d6513c752f96 Type: VM
2014-06-06 17:18:19,301 INFO  [org.ovirt.engine.core.bll.MultipleActionsRunner] (ajp-/127.0.0.1:8702-20) MultipleActionsRunner of type AddVmInterface invoked with no actions