error installing rosserial arduino

edit

i'm following the rosserial_arduino/ Tutorials/ Arduino IDE Setup

I run the first line : hg clone https://kforge.ros.org/rosserial/hg rosserial , and it works well

but when i gonna run the second line about dependencies : rosdep install rosserial_arduino i obtained this ERROR:

ERROR: the following packages/stacks could not have their rosdep keys resolved to system dependencies: rosserial_arduino: Missing resource std_msgs ROS path [0]=/opt/ros/fuerte/share/ros ROS path [1]=/home/moni/fuerte_workspace ROS path [2]=/home/moni/rosserial ROS path [3]=/home/moni/rosserial/rosserial_arduino

i was trying to change de directory of ros path.. but i don't know why doesn't work.

Please Help! it's Urgent!