diff --git a/build/macsyma.tcl b/build/macsyma.tcl
index a4fbe503..fc4768f9 100644
--- a/build/macsyma.tcl
+++ b/build/macsyma.tcl
@@ -276,7 +276,7 @@ respond_load "(load \"libmax;define\")"
 respond_load "(load \"libmax;maxmac\")"
 respond_load "(load \"libmax;displm\")"
 respond_load "(load \"aljabr;loader\")"
-respond "T" "(loader 1000)"
+respond "T" "(loader 1001)"
 respond "(C1)" "quit();"
 
 respond "*" ":copy aljabr;user profil,macsym;\r"
diff --git a/src/jpg/suprv.642 b/src/jpg/suprv.643
similarity index 99%
rename from src/jpg/suprv.642
rename to src/jpg/suprv.643
index 495e8851..9b899c97 100644
--- a/src/jpg/suprv.642
+++ b/src/jpg/suprv.643
@@ -2,6 +2,9 @@
 
 ;   ** (c) Copyright 1976, 1983 Massachusetts Institute of Technology **
 
+;; 2019-03-24 (ejs): Uncommented definition of NONVARCHK since without it
+;;   integration doesn't work.
+
 (macsyma-module suprv)
 
 ;; #+MACLISP is ITS, Twenex, or Multics MacLisp.
@@ -1443,11 +1446,11 @@
   (UNLESS (SYMBOLP X)
 	  (MERROR "The argument to ~:M must be a symbolic name:~%~M" FN X)))
 
-;(DEFMFUN NONVARCHK (X FN FLAG 2NDP)
-;  (WHEN (OR (MNUMP X) (INTEGERP X) (AND FLAG (ATOM X) (CONSTANT X))
-;	    (AND (NOT (ATOM X)) (NOT (EQ (CAAR X) 'MQAPPLY)) (MOPP1 (CAAR X))))
-;	(MERROR "Non-variable~Margument to ~:M: ~M"
-;		(IF 2NDP '|& 2nd | '|& |) FN X)))
+(DEFMFUN NONVARCHK (X FN FLAG 2NDP)
+  (WHEN (OR (MNUMP X) (INTEGERP X) (AND FLAG (ATOM X) (CONSTANT X))
+	    (AND (NOT (ATOM X)) (NOT (EQ (CAAR X) 'MQAPPLY)) (MOPP1 (CAAR X))))
+	(MERROR "Non-variable~Margument to ~:M: ~M"
+		(IF 2NDP '|& 2nd | '|& |) FN X)))
 
 (DEFMFUN PRINL (L) (DOLIST (X L) (PRINC X) (TYO #\SP)))
 
@@ -2751,4 +2754,4 @@ Do you want more?
 (DECLARE (NOTYPE I N N1 N2 U1))
 
 (EVAL-WHEN (EVAL COMPILE) (SETQ BASE OLD-BASE IBASE OLD-IBASE))
-
\ No newline at end of file
+