posibilities of I2C and Digital signal on I've XBEE S2C module and grove development board.

I’ve XBEE S2C module on a grove development board with a gateway running successfully with analog sensors. Is it also possible to connect a grove digital temperature/humidity sensor or a I2C light sensor to these boards?

Only if you use the programmable versions of the XBee module. The reason for that is that the XBee’s RF processor does not support I2C but the programmable versions allow you to write an app that allows the 2nd processor the ability to read I2C inputs.

I thought so. Thanks. And what about this one: http://wiki.seeedstudio.com/wiki/Grove_-_Temperature_and_Humidity_Sensor_Pro

That also appears to be connecting to a I2C connection on either an Arduino