No, it is not. There is an implicit tax on all transactions in future claims unless the claims are issued by the blockchain itself. This has been discussed in this thread and my thread on "securing contingent claims"
I guess what you're wanting then is what was suggested earlier of a bondcoin backed by the bitcoin chain.
Bitcoin wasn't really created to take on all functions of a market (at least I believe that). It is the digital equivalent to gold.
It's entire purpose it to open up a new canvas of money aside from the traditional system and change the perception of who should control money.
This looks a little hard to implement or not even worthwhile in the main bitcoin chain, so I would suggest getting it implemented in the testcoin chain and seeing if there is a demand for bondcoins.
https://en.bitcoin.it/wiki/TestnetI'm sure if enough people get into the idea it could become possible from a free enterprise perspective.
There's even a post about it:
http://forum.bitcoin.org/index.php?topic=7219.0