--- rest.tcl	2016-02-16 22:25:52.048007480 +0000
+++ /usr/lib64/tcl8.5/tcllib1.17/rest/rest.tcl	2016-02-16 22:27:24.149745284 +0000
@@ -486,7 +486,7 @@
             lappend data [dict get $token(meta) Location]
         }
         http::cleanup $t
-        $usercb ERROR $data
+        {*}$usercb ERROR $data
         return
     }
     set data [http::data $t]
