An OSGi BundleActivator is included.

h2/src/main/org/h2/Driver.java

@@ -32,15 +32,12 @@ import org.h2.message.TraceSystem;
 public class Driver implements java.sql.Driver {
 
     private static final Driver INSTANCE = new Driver();
+    private static volatile boolean registered;
 
     static {
-        try {
-            DriverManager.registerDriver(INSTANCE);
-        } catch (SQLException e) {
-            TraceSystem.traceThrowable(e);
-        }
+        load();
     }
-
+    
     /**
      * This method should not be called by an application.
      *
@@ -108,8 +105,30 @@ public class Driver implements java.sql.Driver {
     /**
      * INTERNAL
      */
-    public static Driver load() {
+    public static synchronized Driver load() {
+        try {
+            if (!registered) {
+                registered = true;
+                DriverManager.registerDriver(INSTANCE);
+            }
+        } catch (SQLException e) {
+            TraceSystem.traceThrowable(e);
+        }
         return INSTANCE;
     }
+    
+    /**
+     * INTERNAL
+     */
+    public static synchronized void unload() {
+        try {
+            if (registered) {
+                registered = false;
+                DriverManager.deregisterDriver(INSTANCE);
+            }
+        } catch (SQLException e) {
+            TraceSystem.traceThrowable(e);
+        }
+    }
 
 }

h2/src/main/org/h2/tools/DbDriverActivator.java

+/*
+ * Copyright 2004-2008 H2 Group. Multiple-Licensed under the H2 License, 
+ * Version 1.0, and under the Eclipse Public License, Version 1.0
+ * (http://h2database.com/html/license.html).
+ * Initial Developer: H2 Group
+ */
+package org.h2.tools;
+
+import org.osgi.framework.BundleActivator;
+import org.osgi.framework.BundleContext;
+
+/**
+ * The driver activator loads the H2 driver when starting the bundle.
+ * The driver is unloaded when stopping the bundle.
+ */
+public class DbDriverActivator implements BundleActivator {
+
+    public void start(BundleContext bundleContext) {
+        org.h2.Driver.load();
+    }
+
+    public void stop(BundleContext bundleContext) {
+        org.h2.Driver.unload();
+    }
+
+}

h2/src/test/org/h2/test/jdbc/TestDriver.java

+/*
+ * Copyright 2004-2008 H2 Group. Multiple-Licensed under the H2 License, 
+ * Version 1.0, and under the Eclipse Public License, Version 1.0
+ * (http://h2database.com/html/license.html).
+ * Initial Developer: H2 Group
+ */
+package org.h2.test.jdbc;
+
+import java.sql.DriverManager;
+import java.sql.SQLException;
+
+import org.h2.Driver;
+import org.h2.test.TestBase;
+
+/**
+ * Tests the database driver.
+ */
+public class TestDriver extends TestBase {
+
+    /**
+     * Run just this test.
+     * 
+     * @param a ignored
+     */
+    public static void main(String[] a) throws Exception {
+        TestBase.createCaller().init().test();
+    }
+    
+    public void test() throws Exception {
+        Driver instance = Driver.load();
+        assertTrue(DriverManager.getDriver("jdbc:h2:~/test") == instance);
+        Driver.unload();
+        try {
+            java.sql.Driver d = DriverManager.getDriver("jdbc:h2:~/test");
+            fail(d.toString());
+        } catch (SQLException e) {
+            // ignore
+        }
+        Driver.load();
+        assertTrue(DriverManager.getDriver("jdbc:h2:~/test") == instance);
+    }
+
+}