Sending SOAP Message to IBM DataPower Gateway

Question

I have a problem with sending SOAP Message to IBM DataPower Gateway (I have any instances of DataPower).

I have an app on IBM Websphere Application Server ND, that send SOAP Message to DataPower. But after calling it I get fault Response:

<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:soapenc="http://schemas.xmlsoap.org/soap/encoding/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
    <soapenv:Body>
        <soapenv:Fault>
            <faultcode>soapenv:Server</faultcode>
            <faultstring>javax.net.ssl.SSLHandshakeException: General SSLEngine problem</faultstring>
        </soapenv:Fault>
    </soapenv:Body>
</soapenv:Envelope>

I've found information, that I need in creating signer certificates in WAS ND using "Retrieve from port" with next data:

hostname: dp1host
port:     5550
alias:    dpAlias

I'd done it for one instance of DataPower then it worked for it. But when I try to send SOAP Message to another instance of DataPower, I get the same fault response. I tried to create new signer with next data:

hostname: dp2host
port:     5550
alias:    dpAlias

But I get an error of duplicate signer for using alias. Then I create new alias and repeat my actions with next data:

hostname: dp2host
port:     5550
alias:    dp2Alias

But I get an error of duplicate signer for using alias but with another alias.

Please, help me to send my SOAP Message to any DataPower instances!