Thank you. I really missed one step. After I download the file. ant locales successful.
But when I do ant, it failed. These are the log:
build-mic-check:
[echo] Compiling Microphone Check Application.
[mxmlc] Loading configuration file /home/peng/dev/tools/flex-4.5.0.20967/frameworks/flex-config.xml
[mxmlc] /home/peng/dev/bigbluebutton/bigbluebutton-client/client/MicrophoneCheck.swf (508632 bytes)
build-cam-check:
[echo] Compiling Camera Check Application.
[mxmlc] Loading configuration file /home/peng/dev/tools/flex-4.5.0.20967/frameworks/flex-config.xml
[mxmlc] /home/peng/dev/bigbluebutton/bigbluebutton-client/client/CameraCheck.swf (514221 bytes)
build-conn-check:
[echo] Compiling Connection Check Application.
[mxmlc] Loading configuration file /home/peng/dev/tools/flex-4.5.0.20967/frameworks/flex-config.xml
[mxmlc] /home/peng/dev/bigbluebutton/bigbluebutton-client/client/RTMPConnCheck.swf (510052 bytes)
build-webcam-preview-standalone:
[echo] Compiling webcam preview standalone without optimization.
[mxmlc] Loading configuration file /home/peng/dev/tools/flex-4.5.0.20967/frameworks/flex-config.xml
[mxmlc] /home/peng/dev/bigbluebutton/bigbluebutton-client/client/WebcamPreviewStandalone.swf (514232 bytes)
build-webcam-view-standalone:
[echo] Compiling webcam view standalone without optimization.
[mxmlc] Loading configuration file /home/peng/dev/tools/flex-4.5.0.20967/frameworks/flex-config.xml
[mxmlc] /home/peng/dev/bigbluebutton/bigbluebutton-client/client/WebcamViewStandalone.swf (515804 bytes)
build-bbb-main:
[mxmlc] Loading configuration file /home/peng/dev/tools/flex-4.5.0.20967/frameworks/flex-config.xml
[mxmlc] /home/peng/dev/bigbluebutton/bigbluebutton-client/src/org/bigbluebutton/main/views/MainApplicationShell.mxml(2): col: 1 Error: Content is not allowed in prolog.
[mxmlc]
[mxmlc] n
[mxmlc] ^
[mxmlc]
BUILD FAILED
/home/peng/dev/bigbluebutton/bigbluebutton-client/build.xml:177: The following error occurred while executing this line:
/home/peng/dev/bigbluebutton/bigbluebutton-client/build.xml:294: mxmlc task failed
Total time: 1 minute 8 seconds
Already up-to-date.
Please help out. It is very interesting to work on Ubuntu 13.04.