Index: openacs-4/packages/xowiki/tcl/xowiki-procs.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/xowiki/tcl/xowiki-procs.tcl,v
diff -u -N -r1.485.2.61 -r1.485.2.62
--- openacs-4/packages/xowiki/tcl/xowiki-procs.tcl	21 Mar 2017 14:25:55 -0000	1.485.2.61
+++ openacs-4/packages/xowiki/tcl/xowiki-procs.tcl	15 Apr 2017 10:12:03 -0000	1.485.2.62
@@ -3796,7 +3796,7 @@
       if {[regexp {^(.*[^<>])\s*([=<>]|<=|>=|contains)\s*([^=]?.*)$} $clause _ lhs op rhs_expr]} {
         set lhs [string trim $lhs]
         set rhs_expr [string trim $rhs_expr]
-        if {[string range $lhs 0 0] eq "_"} {
+        if {[string index $lhs 0] eq "_"} {
           #
           # comparison with field names starting with "_"
           #