No 'Connect' string in dump file (4244500)

On a machine where an Oracle instance (e.g. 'TEST') is created by the following command:
Export oracle_sid=TEST Export NLS_LANG=.....Exp system full=y rows=no file=exptest.dmp

When trying to view it in Toad's Database | Export | Export File Browser, no Connect string can be found in the dump file.

1. In the Export File Browser, open the .dmp file
2. Right click on one of the options on the left side of the screen (e.g: Schemas)
3. Select 'Create script from entire export file'

When analysing the script, Toad creates all the objects (system, users etc) with the same logon, however there is no line 'Connect user1/user1' before starting the creation of the objects of the 'user1' owner.