Negative balances in transaction history running public account

[theoreticalbts]

>>> history
TIMESTAMP           BLOCK     FROM                TO                  AMOUNT                  MEMO                                        BALANCE                 FEE                 ID      
==============================================================================================================================================================================================
2014-12-17T23:17:13 1287591   dev0.theoretical    dev0.theoretical    0.00000 BTS             publish version v0.4.27.1                   -0.50000 BTS            0.50000 BTS         f9a26954
2014-12-19T18:35:25 1302262   dev0.theoretical    BTS7AG85XpmRkwh1... 5.00000 BTS             withdraw pay                                -0.60000 BTS            0.10000 BTS         3680d909
2014-12-19T20:22:24 1302891   dev0.theoretical    titan0.theoretical  1.00000 BTS             withdraw pay                                -0.70000 BTS            0.10000 BTS         3d7584c4
2014-12-19T20:26:54 1302918   dev0.theoretical    titan0.theoretical  2,000.00000 BTS         withdraw pay                                -0.80000 BTS            0.10000 BTS         1ce3186e

This is a public account and also a 100% delegate.

I believe there is client and blockchain support to automatically use accumulated delegate pay to cover fees. It appears that fees are being taken from delegate pay balance in preference to my actual balance; I'm not sure whether this is desirable or not.

I think I sent 2 BTS to the account in one transaction, not sure about the txid but it does not show up in history. Maybe history building doesn't work for public accounts, or maybe it requires tx scanning to be enabled (which it is not since I'm a delegate)?

[vikramrajkumar]

Part of current problematic transaction scanner; will try to address as part of #845.