a error about datasource in struts system

[zhu weijian]

my struts-config.xml config information show bellow:
<data-source type="org.apache.commons.dbcp.BasicDataSource">
<set-property property="minCount" value="10" />
<set-property property="password" value="woven" />
<set-property property="maxCount" value="1000" />
<set-property property="user" value="sa" />
<set-property property="driverClass" value="com.microsoft.jdbc.sqlserver.SQLServerDriver" />
<set-property property="description" value="coennect to database..." />
<set-property property="url" value="jdbc:microsoft:sqlserver://192.168.0.100:1433/zb" />
<set-property property="autoCommit" value="false" />
<set-property property="readOnly" value="false" />
<set-property property="loginTimeout" value="500000" />
</data-source>

a error to show below:
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:324)
at org.apache.commons.beanutils.PropertyUtils.setSimpleProperty(PropertyUtils.java:1789)
at org.apache.commons.beanutils.PropertyUtils.setNestedProperty(PropertyUtils.java:1684)
at org.apache.commons.beanutils.PropertyUtils.setProperty(PropertyUtils.java:1713)
at org.apache.commons.beanutils.BeanUtils.setProperty(BeanUtils.java:1019)
at org.apache.commons.beanutils.BeanUtils.populate(BeanUtils.java:808)
at org.apache.struts.action.ActionServlet.initModuleDataSources(ActionServlet.java:1083)
at org.apache.struts.action.ActionServlet.init(ActionServlet.java:472)
at javax.servlet.GenericServlet.init(GenericServlet.java:211)
at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1019)
at org.apache.catalina.core.StandardWrapper.load(StandardWrapper.java:862)
at org.apache.catalina.core.StandardContext.loadOnStartup(StandardContext.java:3991)
at org.apache.catalina.core.StandardContext.start(StandardContext.java:4335)
at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:823)
at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:807)
at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:595)
at org.apache.catalina.core.StandardHostDeployer.install(StandardHostDeployer.java:277)
at org.apache.catalina.core.StandardHost.install(StandardHost.java:832)
at org.apache.catalina.startup.HostConfig.deployDirectories(HostConfig.java:687)
at org.apache.catalina.startup.HostConfig.deployApps(HostConfig.java:432)
at org.apache.catalina.startup.HostConfig.start(HostConfig.java:968)
at org.apache.catalina.startup.HostConfig.lifecycleEvent(HostConfig.java:349)
at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:119)
at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1091)
at org.apache.catalina.core.StandardHost.start(StandardHost.java:789)
at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1083)
at org.apache.catalina.core.StandardEngine.start(StandardEngine.java:478)
at org.apache.catalina.core.StandardService.start(StandardService.java:476)
at org.apache.catalina.core.StandardServer.start(StandardServer.java:2313)
at org.apache.catalina.startup.Catalina.start(Catalina.java:556)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:324)
at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:284)
at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:422)
Caused by: org.apache.commons.dbcp.SQLNestedException: Cannot create JDBC driver of class '' for connect URL 'jdbc:microsoft:sqlserver://192.168.0.100:1433/yqzb'
at org.apache.commons.dbcp.BasicDataSource.createDataSource(BasicDataSource.java:780)
at org.apache.commons.dbcp.BasicDataSource.setLoginTimeout(BasicDataSource.java:586)
... 39 more
Caused by: java.sql.SQLException: No suitable driver
at java.sql.DriverManager.getDriver(DriverManager.java:243)
at org.apache.commons.dbcp.BasicDataSource.createDataSource(BasicDataSource.java:773)
... 40 more

I have add the three MS SQL JDBC jar files's path to classpath
why do show this error ?