In EthereumJ, I have two contracts i deployed them individually,first one was deployed but for the second i got error as in that i was calling function of first one and example i have second is first ,means i am inheriting first one but it showed me error Identifier not found or not unique for first. (I tried with geth it was working fine.)
You should import parent contract/interface like:
If you already have import, make sure the path is correct. I had to remove leading
./ before the file name to make it work at some point.
And then you will have to deploy only one contract. The one witch actually implements the interface, the bytecode of any parent contract will be included in the child to be deployed.