关于apache cxf 结合Spring框架开发webservice服务

我在用apache cxf 结合Spring框架开发webservice服务时，遇到一个这样的问题，请大家帮忙解决一下，问题描述如下：

webservice启动配置如下

<beans xmlns="http://www.springframework.org/schema/beans" 
	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
	xmlns:jaxws="http://cxf.apache.org/jaxws" 
	xsi:schemaLocation="http://www.springframework.org/schema/beans 
	http://www.springframework.org/schema/beans/spring-beans.xsd 
	http://cxf.apache.org/jaxws http://cxf.apache.org/schemas/jaxws.xsd">
	
	<import resource="classpath:META-INF/cxf/cxf.xml" />
	<import resource="classpath:META-INF/cxf/cxf-extension-soap.xml" />
	<import resource="classpath:META-INF/cxf/cxf-servlet.xml" />	
	<jaxws:endpoint id="sqlExecuteService"
		implementor="com.unicom.uniformdata.SqlExecuteServiceImpl"		
		address="/DesServer">	
	</jaxws:endpoint>
</beans>

com.unicom.uniformdata.SqlExecuteServiceImpl类实现如下

@javax.jws.WebService(
                      serviceName = "SqlExecuteServiceService",
                      portName = "SqlExecuteServicePort",
                      targetNamespace = "http://uniformdata.unicom.com",
                      endpointInterface = "com.unicom.uniformdata.SqlExecuteService")
                      
public class SqlExecuteServiceImpl implements SqlExecuteService {
	private DaoHelper daoHelper = null;

	public SqlExecuteServiceImpl() {
		System.out.println("实例化webservice实现类");
		this.daoHelper =  GlobalVariable.getInstance().getDaoHelper();		
	}
}

public DaoHelper getDaoHelper() {
		return this.daoHelper == null ? (this.daoHelper = (DaoHelper) SpringUtils.getBean("daoHelper")): this.daoHelper;
	}

其中daoHelper类的配置是通过<bean>配置的，是数据库操作对象。但在Tomcat启动时，是先实例化SqlExecuteServiceImpl，而不是daoHelper，导致SqlExecuteServiceImpl实例化失败，webservice服务启动失败。这个问题怎么解决。对cxf框架也不是很熟，希望大家能帮助解决一下，谢谢！