Service for sending SMS and making Voice Calls from Web site and Desktop application

问题

We plan to integrate sending of SMS and making calls to our desktop and web applications. Both are written in Java.

As for only sending SMS we know about great gateway from Clickatell. But ideally, we would like to use one service similar to it, but which supports Voice Calls and SMS.

What service/gateway could you recommend? Here are our main requirements:

Reliable
Work world wild (if not, at least Europe operators must be supported)
Providing external API (for SMS) and reusable components (for Voice Calls) which can be integrated with Desktop and Web Java-based applications
Providing sending SMS and making Voice Calls

If there is no service which supports SMS and Voice Calls, we will try to integrate two various services with our products. So, if you know reliable services either for sending SMS or making Voice Calls, please, write about them also. Thanks for your answers.