my $som = $soap->call(
    'CheckForSoftwareUpdates',
    SOAP::Data->name('InstalledSoftware')->value(
        \SOAP::Data->value([
            SOAP::Data->name('SoftwareName')->value('SampleSoftware1'),
            SOAP::Data->name('Version')->value('1.2.3'),
            SOAP::Data->name('OperatingSystem')->value('Windows_XP'),
            ])
        )
    );