SoapVar and Case sensitivity

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Hi all,

I'm trying to access to a Soap web service (written in .Net) using my 
php server (Apache 2.4.3 Win32, PHP 5.4.7) and class "SoapClient"
When I call a soap method, and see my sent data all tags names are in 
lowercase.
Here an example :

Client->MYCall(new SoapVar($this->mUserName, XSD_STRING, "string", 
"http://www.w3.org/2001/XMLSchema", "UserName", "http://[MY-ns]"));

The resulting request :

<soap-env:envelope 
xmlns:soap-env="http://schemas.xmlsoap.org/soap/envelope/" 
xmlns:xsd="http://www.w3.org/2001/XMLSchema" 
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:ns1="MyNS">
<soap-env:body>
<MYCall>
<ns1:username xsi:type="xsd:string">JhonDoe</ns1:username>
</MYCall>
</soap-env:body>
</soap-env:envelope>

If you see the UserName is in lower case in the xml request whereas I 
write it using capitals.

Does some one has a tip for this ?

Thanks in advance

BR.

Mokhtar

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