OLE DOCS...

Variants by reference

Some OLE servers expect parameters passed by reference so that they can be
changed in the method call. This allows methods to easily return multiple
values. There is preliminary support for this in the Win32::OLE::Variant module:

        my $x = Variant(VT_I4|VT_BYREF, 0);
        my $y = Variant(VT_I4|VT_BYREF, 0);
        $Corel->GetSize($x, $y);
        print "Size is $x by $y\n";