Index: openacs-4/packages/acs-datetime/tcl/acs-datetime-procs.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/acs-datetime/tcl/acs-datetime-procs.tcl,v
diff -u -N -r1.18 -r1.19
--- openacs-4/packages/acs-datetime/tcl/acs-datetime-procs.tcl	23 Jul 2018 12:54:26 -0000	1.18
+++ openacs-4/packages/acs-datetime/tcl/acs-datetime-procs.tcl	24 Jul 2018 08:24:07 -0000	1.19
@@ -151,7 +151,7 @@
     }
 
     # get initial calculations to set year, month, day
-    incr calc 1524
+    set calc [expr {$calc + 1524}]
     set calc2 [expr {floor(6680 + (($calc - 2439870) - 122.1) / 365.25)}]
     set calc3 [expr {floor($calc2 * 365.25)}]
     set calc4 [expr {floor(($calc - $calc3) / 30.6001)}]