According documentation, if attribute "StartAtStartup" of ScheduleManager is set to false, the service should not trigger, which happends regardless the state of the element.

I've create a very simple test project similar to ExampleHelloWorldService:

The Management Interface:

package com.demo;

public interface HelloWorldServiceMBean extends ServiceMBean{
public void perform(Date now, long remainingRepetitions);
}

The Service Implementation:

package com.demo.mbean;

public class HelloWorldService extends ServiceMBeanSupport implements HelloWorldServiceMBean{

public void perform( Date now, long remainingRepetitions )

{ log.info( "[perform]: " + now.toString() ); }

}

The deployment descriptor (jboss-service.xml):

<server>
<mbean code="org.jboss.varia.scheduler.ScheduleManager"
name="jboss:service=ScheduleManagerDemo">

<attribute name="StartAtStartup">false</attribute>
</mbean>

<mbean code="com.demo.mbean.HelloWorldService"
name="com.demo:service=HelloWorldService">
</mbean>

<mbean code="org.jboss.varia.scheduler.SingleScheduleProvider"
name="jboss:service=HAImportScheduleProviderDemo">

<depends>jboss:service=ScheduleManagerDemo</depends>
<depends>com.demo:service=HelloWorldService</depends>

<attribute name="ScheduleManagerName">jboss:service=ScheduleManagerDemo</attribute>
<attribute name="TargetName">com.demo:service=HelloWorldService</attribute>
<attribute name="TargetMethod">perform( DATE, REPETITIONS )</attribute>
<attribute name="DateFormat" />
<attribute name="StartDate">NOW</attribute>
<attribute name="Period">2000</attribute>
<attribute name="Repetitions">-1</attribute>
</mbean>
</server>

And everything deployed in a sar file with the following structure:

hello-world.sar

hello-world.sar/META-INF/jboss-service.xml
hello-world.sar/com/demo/HelloWorldService.class
hello-world.sar/com/demo/HelloWorldServiceMBean.class

Despite the element StartAtStartup of ScheduleManager is set to false, the service trigger anyway.