Call https web service with cert

Sorry for my poor english, but i don't know hot to use a SecurityManager with SDK > 3.0.0. I want to call web service over https with x509 cert. I've used so far ti.certificatestore, but after upgrade sdk this won't work.

var certStore = require('ti.certificatestore');        
     certStore.addTrustCertificate('server.cer');
         certStore.addKeyCertificate('client.p12','pass');
         xhr.addTrustManager(certStore.getTrustManager());
         xhr.addKeyManager(certStore.getKeyManager());