MOSS: Deleting Web Application in Central Administration Fails

If you have a Web application in MOSS (or WSS) and you try to delete it from Application Management --> Delete Web Application, you get the following error:

This operation uses the SharePoint Administration service (spadmin), which could not be contacted. If the service is stopped or disabled, start it and try the operation again. at Microsoft.SharePoint.Administration.SPWebApplication.UnprovisionIisWebSitesThroughAdministrationService(Boolean deleteWebSites, String[] serverComments, String applicationPoolId) at Microsoft.SharePoint.Administration.SPWebApplication.UnprovisionIisWebSites(Boolean deleteWebSites, String[] serverComments, String applicationPoolId) at Microsoft.SharePoint.ApplicationPages.DeleteWebApplicationPage.BtnSubmit_Click(Object sender, EventArgs e) at System.Web.UI.WebControls.Button.OnClick(EventArgs e) at System.Web.UI.WebControls.Button.RaisePostBackEvent(String eventArgument) at System.Web.UI.Page.RaisePostBackEvent(IPostBackEventHandler sourceControl, String eventArgument) at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint)

Reason? The user logged in is not an administrator on the Web server. Check out this KB article.