This week's book giveaway is in the OCAJP 8 forum. We're giving away four copies of OCA Java SE 8 Programmer I Study Guide and have Edward Finegan & Robert Liguori on-line! See this thread for details.
"package commonj.sdo does not exis"
In common cases means that jar file containing such package is not found by compiler. Please provide compiler with this jar file (either by copying it in class path or specifying via javac parameter -classpath)
If Zandis' suggestion doesn't help you solve the problem, please post the contents of your build.xml file, and give the full path name for either the commonj.sdo.DataObject class file of the JAR containing that class file.