code: public void domain_changeDnsMXFilter_POST(String domain, String customTarget, OvhDomainMXFilterEnum mxFilter, String subDomain) throws IOException {
  		String qPath = "/email/domain/{domain}/changeDnsMXFilter";
  		StringBuilder sb = path(qPath, domain);
  		HashMap<String, Object>o = new HashMap<String, Object>();
  		addBody(o, "customTarget", customTarget);
  		addBody(o, "mxFilter", mxFilter);
  		addBody(o, "subDomain", subDomain);
  		exec(qPath, "POST", sb.toString(), o);
  	}
docs: Change MX filter, so change MX DNS records
  
  REST: POST /email/domain/{domain}/changeDnsMXFilter
  @param subDomain [required] Sub domain
  @param mxFilter [required] New MX filter
  @param customTarget [required] Target server for custom MX
  @param domain [required] Name of your domain name