Amfphp and "Client.Error.DeliveryInDoubt" error

While working on a recent Flex application that uses amfphp remoting to get data back from the database, I came across the following error:

[RPC Fault faultString="Channel disconnected" faultCode="Client.Error.DeliveryInDoubt" faultDetail="Channel disconnected before an acknowledgement was received"]

After several hours of googling for the solution, couldn't find anything.
So, I just started changing the method signatures on my PHP functions and finally, I was able to get this thing to work.

The key is to change the php function to accept a parameter of "Object" type, i.e., an array of name-value pairs.

Intially my method signature looked like the following:

public function getSchools($districId, $zipCode) {
....
}

Then, I changed it to the following and every thing worked like a charm.
public function getSchools($args) {
$districId = $args['districId'];
$zipCode = $args['zipCode'];
....
}

It was tha simple.

I also had to change the Remote Object method call inside my Flex application from :

srv.getSchools(districId, zipCode);


To, the following:
var params:Object = new Object();
params.districId = String(districId);
params.zipCode = String(zipCode);
srv.getSchools(params);


I think you can fix similar errors in Zend Framework or WebOrb remoting also, although, I have tested those myself.

That was all. Happy Flexing.