diff --git a/perl/FKO/lib/FKO.pm b/perl/FKO/lib/FKO.pm
index 377f6f33..fb17b633 100644
--- a/perl/FKO/lib/FKO.pm
+++ b/perl/FKO/lib/FKO.pm
@@ -265,13 +265,13 @@ sub spa_client_timeout {
 
 sub spa_digest {
     my $self = shift;
-    my $val  = shift;
     my $recompute = shift || 0;
 
+    my $val = '';
+
     return FKO::_set_spa_digest($self->{_ctx})
         if($recompute);
 
-    $val = '';
     $self->{_err} = FKO::_get_spa_digest($self->{_ctx}, $val);
 
     return($self->_check_return_val($val));