1.) You will need to register your Sina Weibo with Mail2Weibo (http://m2w.21du.cn) 2.) Use the address generated by Mail2Weibo as recipient of the outgoing mail of your gmail account. Voilá, your Twitter will synch with Sina Weibo via Mail2Weibo.

This Trigger fires every time you post a new tweet.

This Action will send an email to up to twenty recipients from your Gmail account.

Twitter to Sina Weibo via Gmail