fixed issue 1247 Missing URL for Delete button, thanks Boris and Niphlod

gluon/html.py

@@ -1478,9 +1478,9 @@ class A(DIV):
                 (self['component'], self['target'] or '', d)
             self['_href'] = self['_href'] or '#null'
         elif self['callback']:
-            returnfalse = "var e = arguments[0] || window.event; e.cancelBubble=true; if (e.stopPropagation) e.stopPropagation();"
+            returnfalse = "var e = arguments[0] || window.event; e.cancelBubble=true; if (e.stopPropagation) e.stopPropagation(); e.preventDefault();"
             if d:
-                self['_onclick'] = "if(confirm(w2p_ajax_confirm_message||'Are you sure you want o delete this object?')){ajax('%s',[],'%s');%s};%s" % \
+                self['_onclick'] = "if(confirm(w2p_ajax_confirm_message||'Are you sure you want to delete this object?')){ajax('%s',[],'%s');%s};%s" % \
                     (self['callback'], self['target'] or '', d, returnfalse)
             else:
                 self['_onclick'] = "ajax('%s',[],'%s');%sreturn false" % \