Virtual Ethernet with VIO

We're using VIO (not an HMC) to manage our LPAR's We have 3 physical adapters and 4 LPARs. Through the VIO interface we assigned 2 virtual interfaces but require a 3rd interface assigned to these LPARs. I am experiencing issues understanding exactly how to create another virtual adapter, either within VIO web interface or vio cli.

My configuration looks like this:
ent2 Available Virtual I/O Ethernet Adapter (l-lan)
ent3 Available Virtual I/O Ethernet Adapter (l-lan)
ent4 Available Virtual I/O Ethernet Adapter (l-lan)
ent5 Available Virtual I/O Ethernet Adapter (l-lan)
ent0 Available 08-08 2-Port 10/100/1000 Base-TX PCI-X Adapter (14108902)
ent1 Available 08-09 2-Port 10/100/1000 Base-TX PCI-X Adapter (14108902)
ent8 Available 0B-08 10/100/1000 Base-TX PCI-X Adapter (14106902)
ent6 Available Shared Ethernet Adapter
ent7 Available Shared Ethernet Adapter
ent9 Available Shared Ethernet Adapter

I do not think I need to setup an additional shared enternet to create the virtual adapter but this is where I am not sure how to proceed. I have tried to issue the mkvdev -sea ent0 -vadapter ent10 -default ent10 -defaultid 1 command but receive the following error:

"Some error messages may contain invalid information
for the Virtual I/O Server environment.

Method error (/usr/lib/methods/chgsea):
0514-018 The values specified for the following attributes
are not valid:
pvid_adapter

Command did not complete.

"Run mkdev" was last subcommand run."

I'm sure I am missing something very simple but at this point I've exhausted my resources. All the redbooks and manuals I've found refer to using an HMC and we're not using one. Any information as to where else to look or how to create the virtual ethernet adapters is appreciated.

Please run the following command as padmin:

lsmap -all -net

Then post the result here so I can analyse it. You might check yourself to see if ent0 (en0 or et0) is already being used.