Hi, I'm having a problem building a package that has serial_port as a dependency. When I run 'rosmake', I get the following message in the terminal: [rosbuild] Building package serial_port [rosbuild] Including /opt/ros/cturtle/ros/core/rospy/cmake/rospy.cmake [rosbuild] Including /opt/ros/cturtle/ros/core/roscpp/cmake/roscpp.cmake [rosbuild] Including /opt/ros/cturtle/ros/core/roslisp/cmake/roslisp.cmake -- Configuring done CMake Error: Unable to open cache file for save. /opt/ros/cturtle/stacks/serial_port/build/CMakeCache.txt CMake Error: : System Error: Permission denied I've made sure that all users/groups/etc have read/write access to the CMakeCache.txt file, but it still doesn't seem to work. I'm using cturtle with the serial_port package, output from 'uname -a': Linux robot-brain 2.6.32-25-generic #44-Ubuntu SMP Fri Sep 17 20:26:08 UTC 2010 i686 GNU/Linux Any help is greatly appreciated.