Fixed bug in TextSession that caused crash when summarising balance movement of pure envelope Accounts.
Fixed bug in TextSession that caused crash when summarising balance movement of pure envelope Accounts.

git-svn-id: 0231d2b9506727b8389b50bfeac72ec1f38c13c1@1223 ac3cbfda-f6ac-4daa-b570-d46c5f00fc98

skybaboon/dailycashmanager,skybaboon/dailycashmanager,skybaboon/dailycashmanager