Getting Unsupported AMF version 20,555 while attempting to upload a file in Flex protocal

Hi,

I'm getting the following return message from the server  while attempting to upload a file in Flex protocal:

SIflex.messaging.messages.ErrorMessageheadersrootCause    bodycorrelationIdfaultDetailfaultStringclientIdtimeToLivedestinationtimestampextendedDatafaultCodemessageId
?Unsupported AMF version 20,555.

This is my function I am using to upload the file:

web_custom_request("amfssl_22",
        "URL=www.testurl.com", 
        "Method=POST", 
        "Resource=0", 
        "RecContentType=application/x-amf", 
        "Referer=https://testurl.com/dvclient/DVantage.swf?swf-version=12345678", 
        "Snapshot=t50.inf", 
        "Mode=HTML", 
        "EncType=application/x-amf", 
        "BodyFilePath=C:\\Users\\jzk0dr\\Documents\\Perf_Test - Large.docx", 
        LAST);

Can anyone help with this?

Thanks,

RyanV