vcard.addImpp(new ImppType("im:alice@example.com"));
vcard.addImpp(new ImppType(new URI("im:alice2@example.com")));
ImppType impp = new ImppType();
impp.setUri(new URI("im:alice3@example.com"));
impp.addParam(ImppParamType.HOME)
.addParam(ImppParamType.PREF)
.addExtendedParam(new ExtendedParamType("X-BLA", "BLE", VCardTypeName.IMPP));
vcard.addImpp(impp);
((VCardErrorHandler)vcard).setThrowExceptions(false);