can't return special type DomDocument xml

[fidelio314]

Hi!
I have set up the controller for SoapServer,
on my action i have set:
@soap\Result(phpType = "DOMDocument") on the annotations.
in my action i get a Xml whitch i try to return!
like:
return $this->container->get('besimple.soap.response')->setReturnValue($xml);
or
return $xml

But i can't get to have the xml as response!

i tried event with
@soap\Result(phpType = "string")

i always get this kind of error:
[SoapFault] looks like we got no XML document

could't please post an exemple on handling a Xml return?

thank you for the help, in advance!

[fidelio314]

may be a memory_limit issue.
i abandoned BeSimpleSoapBundle, i did the way Symfony's documentation explains, through a controller and the use of a service.
i had the same error...

i set: ini_set('memory_limit', '-1');

and the problem was solved.

for this issue thought i still don't know if we need to return a XML should we do it with a phpType string?

thanks