oracle connect ; manual eror handling

[JONL]

Have been connecting to oracle using the following with success
my $dbHandle = DBI->connect($sConnectString, $sUsername, $sPassword );
adding ,\%attr after password permits me to set the db handle options

But now we use a different connect syntax to support OS authentication:
my $sLoginString = "$sUsername/$sPassword";
my $dbHandle = DBI->connect($sConnectString, $sLoginString) ;

this will work but if I add \%attr after the LoginString, the connect
complains that I gave it an empty password. What I need to be able to
do is to use the second syntax but still be able to set dbh options.
ANy ideas?