diff --git a/src/vm.c b/src/vm.c
index 8e2ddb6c..39e0d6f8 100644
--- a/src/vm.c
+++ b/src/vm.c
@@ -51,6 +51,7 @@ pic_get_proc(pic_state *pic)
  *  l   lambda object
  *  p   port object
  *  d   dictionary object
+ *  e   error object
  *
  *  |  optional operator
  *  *  variable length operator
@@ -346,8 +347,25 @@ pic_get_args(pic_state *pic, const char *format, ...)
       }
       break;
     }
+    case 'e': {
+      struct pic_error **e;
+      pic_value v;
+
+      e = va_arg(ap, struct pic_error **);
+      if (i < argc) {
+        v = GET_OPERAND(pic,i);
+        if (pic_error_p(v)) {
+          *e = pic_error_ptr(v);
+        }
+        else {
+          pic_error(pic, "pic_get_args, expected error");
+        }
+        i++;
+      }
+      break;
+    }
     default:
-      pic_error(pic, "pic_get_args: invalid argument specifier given");
+      pic_errorf(pic, "pic_get_args: invalid argument specifier '%c' given", c);
     }
   }
   if ('*' == c) {