To override the Content-type in your clients, use the HTTP Accept Header, append the .xml suffix or ?format=xml
The following are sample HTTP requests and responses. The placeholders shown need to be replaced with actual values.
POST /xml/reply/SetCrmOrderProductWhCollected[] HTTP/1.1
Host: 10.10.0.107
Accept: application/xml
Content-Type: application/xml
Content-Length: length
<ArrayOfSetCrmOrderProductWhCollected xmlns:i="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://schemas.datacontract.org/2004/07/Apex.Services.Crm.Orders">
<SetCrmOrderProductWhCollected>
<OrderProductId>0</OrderProductId>
<SubOrderId>0</SubOrderId>
<OrderId>0</OrderId>
<BCode>String</BCode>
</SetCrmOrderProductWhCollected>
</ArrayOfSetCrmOrderProductWhCollected>
HTTP/1.1 200 OK
Content-Type: application/xml
Content-Length: length
<ArrayOfSetCrmOrderProductWhCollectedResponse xmlns:i="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://schemas.datacontract.org/2004/07/Apex.Services.Crm.Orders">
<SetCrmOrderProductWhCollectedResponse>
<ResponseStatus xmlns:d3p1="http://schemas.servicestack.net/types">
<d3p1:ErrorCode>String</d3p1:ErrorCode>
<d3p1:Message>String</d3p1:Message>
<d3p1:StackTrace>String</d3p1:StackTrace>
<d3p1:Errors>
<d3p1:ResponseError>
<d3p1:ErrorCode>String</d3p1:ErrorCode>
<d3p1:FieldName>String</d3p1:FieldName>
<d3p1:Message>String</d3p1:Message>
<d3p1:Meta xmlns:d6p1="http://schemas.microsoft.com/2003/10/Serialization/Arrays">
<d6p1:KeyValueOfstringstring>
<d6p1:Key>String</d6p1:Key>
<d6p1:Value>String</d6p1:Value>
</d6p1:KeyValueOfstringstring>
</d3p1:Meta>
</d3p1:ResponseError>
</d3p1:Errors>
<d3p1:Meta xmlns:d4p1="http://schemas.microsoft.com/2003/10/Serialization/Arrays">
<d4p1:KeyValueOfstringstring>
<d4p1:Key>String</d4p1:Key>
<d4p1:Value>String</d4p1:Value>
</d4p1:KeyValueOfstringstring>
</d3p1:Meta>
</ResponseStatus>
<Result>false</Result>
</SetCrmOrderProductWhCollectedResponse>
</ArrayOfSetCrmOrderProductWhCollectedResponse>