geoserver - How to get layer extent in OpenLayers or zoom to WMS layer extent?

I have added WMS layers using follow:

basemap = new OpenLayers.Layer.WMS( "Layer Name1",
"http://localhost:8080/geoserver/wms/workspacename", {layers: 'workspacename:layername'} );  
utility = new OpenLayers.Layer.WMS( "Layer Name2",
"http://localhost:8080/geoserver/wms/workspacename", {layers: 'workspacename:layername', transparent:"true"}, {isBaseLayer:false} );

Now I want to get zoom to my utility layer, How can I?

I have tried as following:

map.zoomToExtent(utility.getDataExtent());