Unable to run any job.

[jazeera]

Don't quite know what happened but we have been seeing every job fail with cryptic messages such as the following:-

Diagnostic Message:- Advanced runtime options used: lsi.readu

and
Error Message :- main_program: A step specification should be the final item; saw: -f.
Error Message :-
main_program: Orchestrate Parallel Command Shell
usage: /usr/ETL/7.5.1a/Ascential/DataStage/PXEngine/bin/osh <options> "<step specification>"
or: /usr/ETL/7.5.1a/Ascential/DataStage/PXEngine/bin/osh <options> -f file [-stdin file]
<options> include: [-echo] [-explain] [-dump] [-schema] [-check]
[-collation_sequence <collation file>]
[-collation_strength <collation strength>]
[-pdd <performance data directory>]
[-pf <parameter file>]
[-nopartinsertion] [-nosortinsertion]
[-params <parameter string>]
[-errorconfig <configstring>] [-jobid <jobid>]
[-restartable [-checkpointdir <dir>] [-segments N] ]
[-nomonitor] [-monitorport <monitor port>]
[-input_charset <map name>] [-output_charset <map name>]
[-string_charset <map name>] [-impexp_charset <map name>]
[-os_charset <map name>]
[-escaped]
[-default_date_format <uformat>]
[-default_time_format <uformat>]
[-default_timestamp_format <uformat>]
[-default_decimal_separator <separator>]
[-string_fields]
or: /usr/ETL/7.5.1a/Ascential/DataStage/PXEngine/bin/osh -usage operatorname
or: /usr/ETL/7.5.1a/Ascential/DataStage/PXEngine/bin/osh -fullusage operatorname
or: /usr/ETL/7.5.1a/Ascential/DataStage/PXEngine/bin/osh -status [-jobid <jobid>] [-checkpointdir <dir>]
or: /usr/ETL/7.5.1a/Ascential/DataStage/PXEngine/bin/osh -resume [-jobid <jobid>] [-checkpointdir <dir>]

Nothing changed in the environment. What could be causing this? Any help will be greatly appreciated.