Roman, i've added jass, log4j-core and mini-j2ee explicity to the
classpath and now i'm getting another exception:

Exceção no encadeamento "main" java.lang.NoClassDefFoundError:
javax.naming.Referenceable
at java.lang.ClassLoader.defineClassImpl(Native Method)
at java.lang.ClassLoader.defineClass(Unknown Source)
at java.security.SecureClassLoader.defineClass(Unknown Source)
at java.net.URLClassLoader.findClassImpl(Unknown Source)
at java.net.URLClassLoader$4.run(Unknown Source)
at java.security.AccessController.doPrivileged(Unknown Source)
at java.net.URLClassLoader.findClass(Unknown Source)
at com.ibm.oti.vm.URLSystemClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at com.ibm.oti.vm.URLSystemClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.defineClassImpl(Native Method)
at java.lang.ClassLoader.defineClass(Unknown Source)
at java.security.SecureClassLoader.defineClass(Unknown Source)
at java.net.URLClassLoader.findClassImpl(Unknown Source)
at java.net.URLClassLoader$4.run(Unknown Source)
at java.security.AccessController.doPrivileged(Unknown Source)
at java.net.URLClassLoader.findClass(Unknown Source)
at com.ibm.oti.vm.URLSystemClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at com.ibm.oti.vm.URLSystemClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)

(The old exception is here!)

at org.firebirdsql.jdbc.FBDriver.createDataSource(Unknown Source)
at org.firebirdsql.jdbc.FBDriver.connect(Unknown Source)
at java.sql.DriverManager.getConnection(Unknown Source)
at java.sql.DriverManager.getConnection(Unknown Source)

(This event is a button wigetSelected())

at br.com.t2tecnologia.HelloComposite1$2.handleEvent(Unknown Source)
at org.eclipse.swt.widgets.EventTable.sendEvent(Unknown Source)
at org.eclipse.swt.widgets.Widget.sendEvent(Unknown Source)
at org.eclipse.swt.widgets.Display.runDeferredEvents(Unknown Source)
at org.eclipse.swt.widgets.Display.readAndDispatch(Unknown Source)
at br.com.t2tecnologia.HelloSWT.main(Unknown Source)

(My app is called HelloSWT)

javax.naming.Referenceable is part of mini-j2ee, but I don't know
what's wrong...
Look how I'm running the app:

"\Program Files\J9\PPRO10\bin\j9.exe" "-jcl:ppro10" "-cp"
"\Temp\jaas.jar;\Temp\mini-j2ee.jar;\Temp\log4j-core.jar;\Temp\jaybird-2.1.0.jar;\Temp\HelloSWT.jar"
"br.com.t2tecnologia.HelloSWT"

And i've tried:

"\Program Files\J9\PPRO10\bin\j9.exe" "-jcl:ppro10"
"-Xbootclasspath/a:\Temp\jaas.jar;\Temp\mini-j2ee.jar;\Temp\log4j-core.jar"
"-cp" "\Temp\jaybird-2.1.0.jar;\Temp\HelloSWT.jar"
"br.com.t2tecnologia.HelloSWT"

Both commands raise same exception.

I'll keep trying, if you see some mistake that I'm doing, please tell me.