If you ever find the need to compile H2 database yourself to install it in your local Maven repository, here are the steps:
svn checkout http://h2database.googlecode.com/svn/trunk/ h2database-read-only
cd h2database-read-only/h2
./build.sh mavenInstallLocal
Your custom H2 build is now installed in your local Maven repository as version 1.0-SNAPSHOT. Include it as a dependency in your project by adding the appropriate XML to your pom.xml:
<project>
...
<dependencies>
...
<dependency>
<groupId>com.h2database</groupId>
<artifactId>h2</artifactId>
<version>1.0-SNAPSHOT</version>
</dependency>
...
</dependencies>
...
</project>
I had to do these steps in order to test a fix I am preparing for H2 to solve the "SET NAMES" syntax error in MySQL compatibility mode when connecting to H2 using the Quercus PHP MySQL driver.