I've tried like this (link):

<taskdef resource="net/sf/antcontrib/antlib.xml" />
<taskdef resource="net/sf/ant4eclipse/antlib.xml" />

<target name="copy_jars">
  <getEclipseClasspath workspace="${basedir}/.."
                       projectname="MyProject"
                       property="classpath"
                       relative="false"
                       runtime="true"
                       pathseparator="#" />

  <!-- iterate over all classpath entries -->
  <foreach list="${classpath}" delimiter="#"
    target="copy_jar_file" param="classpath.entry" />
</target>

<target name="copy_jar_file">
  <!-- check if current is a .jar-file ... -->
  <if>
    <isfileselected file="${classpath.entry}">
      <filename name="**/*.jar" />
    </isfileselected>
    <then>
      <!-- copy the jar file to a destination directory -->
      <copy file="${classpath.entry}" tofile="${dest.dir}"/>
    </then>
  </if>
</target>

But I get the exception:

[getEclipseClasspath] net.sf.ant4eclipse.model.FileParserException: Could not parse plugin project 'E:\...\MyProject' since it contains neither a Bundle-Manifest nor a plugin.xml!
[getEclipseClasspath]  at net.sf.ant4eclipse.model.pdesupport.plugin.PluginDescriptorParser.parseEclipseProject(Unknown Source)
[getEclipseClasspath]  at net.sf.ant4eclipse.model.pdesupport.plugin.PluginProjectRoleIdentifier.applyRole(Unknown Source)
[getEclipseClasspath]  at net.sf.ant4eclipse.model.roles.RoleIdentifierRegistry.applyRoles(Unknown Source)
[getEclipseClasspath]  at net.sf.ant4eclipse.tools.ProjectFactory.readProjectFromWorkspace(Unknown Source)
[getEclipseClasspath]  at net.sf.ant4eclipse.tools.resolver.AbstractClasspathResolver.resolveEclipseClasspathEntry(Unknown Source)
[getEclipseClasspath]  at net.sf.ant4eclipse.tools.resolver.AbstractClasspathResolver.resolveProjectClasspath(Unknown Source)
[getEclipseClasspath]  at net.sf.ant4eclipse.tools.resolver.ProjectClasspathResolver.resolveProjectClasspath(Unknown Source)
[getEclipseClasspath]  at net.sf.ant4eclipse.ant.task.project.GetEclipseClassPathTask.resolvePath(Unknown Source)
[getEclipseClasspath]  at net.sf.ant4eclipse.ant.task.project.AbstractGetProjectPathTask.execute(Unknown Source)
[getEclipseClasspath]  at org.apache.tools.ant.UnknownElement.execute(UnknownElement.java:288)
[getEclipseClasspath]  at sun.reflect.GeneratedMethodAccessor1.invoke(Unknown Source)
[getEclipseClasspath]  at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
[getEclipseClasspath]  at java.lang.reflect.Method.invoke(Method.java:597)
[getEclipseClasspath]  at org.apache.tools.ant.dispatch.DispatchUtils.execute(DispatchUtils.java:105)
[getEclipseClasspath]  at org.apache.tools.ant.Task.perform(Task.java:348)
[getEclipseClasspath]  at org.apache.tools.ant.Target.execute(Target.java:357)
[getEclipseClasspath]  at org.apache.tools.ant.Target.performTasks(Target.java:385)
[getEclipseClasspath]  at org.apache.tools.ant.Project.executeSortedTargets(Project.java:1329)
[getEclipseClasspath]  at org.apache.tools.ant.Project.executeTarget(Project.java:1298)
[getEclipseClasspath]  at org.apache.tools.ant.helper.DefaultExecutor.executeTargets(DefaultExecutor.java:41)
[getEclipseClasspath]  at org.eclipse.ant.internal.ui.antsupport.EclipseDefaultExecutor.executeTargets(EclipseDefaultExecutor.java:32)
[getEclipseClasspath]  at org.apache.tools.ant.Project.executeTargets(Project.java:1181)
[getEclipseClasspath]  at org.eclipse.ant.internal.ui.antsupport.InternalAntRunner.run(InternalAntRunner.java:423)
[getEclipseClasspath]  at org.eclipse.ant.internal.ui.antsupport.InternalAntRunner.main(InternalAntRunner.java:137)

BUILD FAILED
E:\...\build.xml:132: Exception whilst resolving the classpath of project MyProject! Reason: Could not parse plugin project 'E:\...\MyProject' since it contains neither a Bundle-Manifest nor a plugin.xml!

I wan't to copy just the jars, not the referenced projects. Is there a way to parametrize the task getEclipseClasspath so it only gets the jars, not the projects?