Bug #102311 SX - infinite loop in transaction processing

[W. Scott Wilburn]

FWIW, I triggered this when I deleted an account but forgot to delete
a SX for that account.

Manual fixing worked as described, but would be difficult for the
vi/emacs impaired. Seems the real fix is to check SX's when deleting
an account (assuming this is the only way this happens), or giving a
dialog on start that gives options like 'Skip SX', 'Delete SX', etc.