javax.net.ssl.SSLHandshakeException: java.security.cert.CertificateException: 5950
    at com.ibm.jsse2.o.a(o.java:8)
    ...
    at http.HttpConnector.send(Unknown Source)
    at http.HttpConnector.sendPostRequest(Unknown Source)
Caused by: java.security.cert.CertificateException: 5950
    at com.ibm.domino.napi.ssl.DominoX509TrustManager.checkServerTrusted(DominoX509TrustManager.java:98)
    at com.ibm.jsse2.lb.a(lb.java:30)
    ... 19 more

Certificate with subject [certificate info, see further] is not trusted. Validation failed with error 5950.