Webservice returning null values

Webservice returning null values when consuming .net webservice and return datatype is string[].

<mx:WebService id="Content" wsdl="http://www.paxsonmarketing.com/Content.asmx?WSDL">
<mx:operation name="Countries" resultFormat="{ObjectProxy}" result="getCountries_result(event);" fault="getCountries_fault(event);" >
<mx:request>
<AffiliateID>{AffiliateID}</AffiliateID>
<Password>{AffiliatePassword}</Password>
<AvailableOnly>true</AvailableOnly>
</mx:request>
</mx:operation>
</mx:WebService>

Above is what my webservice looks like. Basically I tried to use the Flex 3 Built in 'Data' > 'Import Web services functionality' however this also returned a null values for type.. 'arrayOfString'. I have tested the webservice and it def returns an 'arrayOfString'. I tried the above code as well and it does the same.

I tried other methods to the same webservice and they work if I am not returning type of 'arrayOfString'.

Any Ideas?