Handle for Object Short Text

I could not find a handle for Object Short Text if I want to modify the same. I'm filtering objects and then modifying Object Short text with some information.

almUser - Fri Jul 11 06:35:28 EDT 2014

Re: Handle for Object Short Text
Tony_Goodman - Mon Jul 14 08:36:43 EDT 2014

o."Object Short Text" = "new value"