UpgradeManager references webwork class

On startup, the UpgradeManager class tries to access a webwork class, and since it is in the backend, it cannot see the webwork jar file which is in the web classes, hence blows up:

2002-05-17 00:47:42,602 ERROR [atlassian.jira.upgrade.UpgradeRunner] Exception whilst trying to upgrade: webwork/action/ActionSupport
java.lang.NoClassDefFoundError: webwork/action/ActionSupport
at com.atlassian.jira.upgrade.UpgradeManager.<init>(UpgradeManager.java:43)
at com.atlassian.jira.upgrade.UpgradeRunner.contextInitialized(UpgradeRunner.java:37)
at com.evermind._cp._wcc(.:552)
at com.evermind._cp.<init>(.:348)