Motorola Inc and Shanda Interactive Entertainment Ltd, a Nasdaq-listed Chinese online game company, have formed a partnership under which Shanda will provide games for Motorola's E680g handset, Reuters reporetd.   As the first of its kind in China, Motorola rolled out its E680G, a modified version of an existing gaming handset adapted to play online titles from Shanda. The deal also entails a six-month exclusivity arrangement under which Motorola will not license games from Shanda's competitors and Shanda will not strike similar arrangements with other handset makers.   "Eighty-three percent of China mobile phone users play games on their mobile phones. This is why we've chosen China first," Chapman-Banks, Motorola's North Asia general manager of marketing and business development for mobile devices, told Reuters at ChinaJoy.   Motorola has also simultaneously launched a Chinese game portal with over 350 Java-based titles for Motorola phones. Users can purchase games, with the revenues going to the game developers, Chapman-Banks said.