Pardon my ignorance. Being around for so long I should be knowing this 
I read somewhere that signatures are now (or soon will be) required to be deterministic. Is this true?
If true, will transactions signed by earlier versions of bitcoind/j be accepted?
I read somewhere that signatures are now (or soon will be) required to be deterministic. Is this true?
If true, will transactions signed by earlier versions of bitcoind/j be accepted?
You either misunderstood what you read, or your source was mistaken.
Signatures are not "required" to be deterministic, nor will they be "required" to be deterministic any time soon.
Deterministic signatures are a good idea, so many wallets are now implementing them, but as long as you use a good source of randomness non-deterministic signatures will work just fine.
Note, that it has always been a good idea to use a new bitcoin address for every transaction, and if you followed that advice then it really doesn't matter much whether you use deterministic signatures or not.
Also, the idea of "requiring" only makes sense if it is possible to verify with certainty whether the signature was indeed generated deterministically.
I think unless the client generates two different signatures for the same message we cannot be sure.
So the question also does not make sense.
