Win32::OLE->Option(Warn => 3);
is equivalent to
Win32::OLE->Option(Warn => \&Carp::croak);
This can even be used to emulate the VisualBasic "On Error Goto Label" construct:
Win32::OLE->Option(Warn =>  sub {goto CheckError});
# ... your normal OLE code here ...
CheckError:
# ... your error handling code here ...