OS: Win7 64bit
JDK: Sun JDK 1.7 64bit
Ant: 1.8.4
c3p0: 0.9.5-pre1
mchange-commons: 0.2.4
Notice: Make sure JDK version, c3p0 version and mchange-commons-java jar version is exactly 1.7, 0.9.5 and 0.2.4
Step1: Download or check out source code of c3p-0.9.5 from https://github.com/swaldman/c3p0
Step2. Download mchange-commons-java-0.2.4-sources.jar and mchange-commons-java-0.2.4-.jar
from https://oss.sonatype.org/content/repositories/releases/com/mchange/mchange-commons-java/0.2.4/
Step3. Create a folde named "lib"r under c3p0's source folder. Put mchange-commons-java-0.2.4-sources.jar & mchange-commons-java-0.2.4.jar into lib folder.
Step4. Run ant command in c3p0's source folder.
In short, ( JDK7 && mchange-commons 0.2.4 && c3p0 0.9.5 ) == Build Successful
Special thanks to Steve Waldman who helps me with patience and expertise to solve trouble a newbee met.