[deathanatos]

Does SOAP (or WSDL?) or whatever he is using not store type information with the value? Take JSON, which has null (the actual value) and "Null" (a string) - it isn't ambiguous which you mean.

I feel like if my serialization format couldn't differentiate between those, that'd be a deal-breaker.

[jonny_eh]

Sounds about right to me. That's why I use JSON, it's much more sensible than SOAP.