Index: openacs-4/packages/acs-bootstrap-installer/installer/index.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/acs-bootstrap-installer/installer/index.tcl,v
diff -u -r1.32.2.7 -r1.32.2.8
--- openacs-4/packages/acs-bootstrap-installer/installer/index.tcl	1 Mar 2021 10:46:19 -0000	1.32.2.7
+++ openacs-4/packages/acs-bootstrap-installer/installer/index.tcl	22 Dec 2022 02:51:37 -0000	1.32.2.8
@@ -185,7 +185,7 @@
     }
 }
 
-if { ![string is integer $stacksize]
+if { ![string is integer -strict $stacksize]
      || $stacksize < $acs_application(min_stack_size) * 1024
  } {
     append errors "<li><p><strong>The configured stacksize '$stacksize' is too small, missing, or a non-integer value.
Index: openacs-4/packages/acs-templating/tcl/date-procs.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/acs-templating/tcl/date-procs.tcl,v
diff -u -r1.63.2.20 -r1.63.2.21
--- openacs-4/packages/acs-templating/tcl/date-procs.tcl	7 Nov 2022 13:38:55 -0000	1.63.2.20
+++ openacs-4/packages/acs-templating/tcl/date-procs.tcl	22 Dec 2022 02:51:37 -0000	1.63.2.21
@@ -1693,7 +1693,7 @@
     }
 
     if {[info exists element(step)]} {
-        if {[string is integer $element(step)]} {
+        if {[string is integer -strict $element(step)]} {
             dict set attributes step $element(step)
         } else {
             ns_log Warning {template::widget::h5date value of attribute "step" is not an integer!}
@@ -1846,7 +1846,7 @@
     }
 
     if {[info exists element(step)]} {
-        if {[string is integer $element(step)]} {
+        if {[string is integer -strict $element(step)]} {
             dict set attributes step $element(step)
         } else {
             ns_log Warning {template::widget::h5time value of attribute "step" is not an integer!}
Index: openacs-4/packages/assessment/lib/section-links.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/assessment/lib/section-links.tcl,v
diff -u -r1.3.2.1 -r1.3.2.2
--- openacs-4/packages/assessment/lib/section-links.tcl	18 Aug 2022 15:48:59 -0000	1.3.2.1
+++ openacs-4/packages/assessment/lib/section-links.tcl	22 Dec 2022 02:51:37 -0000	1.3.2.2
@@ -19,11 +19,11 @@
 set questions_url [export_vars -base questions {assessment_id}]
 
 # validate that tab is set properly
-if { ![string is integer $tab] && ($tab ne "front") && ($tab ne "results") && ($tab ne "questions") } {
+if { ![string is integer -strict $tab] && $tab ni {"front" "results" "questions"} } {
     error "lib/section-links: tab should be front, results, questions or a section_id"
 }
 
-if { [string is integer $tab] } {
+if { [string is integer -strict $tab] } {
     set tab questions
 }
 
Index: openacs-4/packages/caldav/tcl/caldav-interface-procs.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/caldav/tcl/caldav-interface-procs.tcl,v
diff -u -r1.1.2.6 -r1.1.2.7
--- openacs-4/packages/caldav/tcl/caldav-interface-procs.tcl	11 Jul 2022 12:45:57 -0000	1.1.2.6
+++ openacs-4/packages/caldav/tcl/caldav-interface-procs.tcl	22 Dec 2022 02:51:37 -0000	1.1.2.7
@@ -119,7 +119,7 @@
         } else {
             set calclause "= :calendar_ids"
         }
-        set e_clause [expr {[string is integer $uid] ? " or e.activity_id = :uid" : ""}]
+        set e_clause [expr {[nsf::is integer $uid] ? " or e.activity_id = :uid" : ""}]
 
         return [::xo::dc list get_cal_item_from_uid [subst {
             select cal_item_id
@@ -166,7 +166,7 @@
             limit 1
         }]
 
-        # set e_clause [expr {[string is integer $uid] ? " or e.activity_id = :uid" : ""}]
+        # set e_clause [expr {[nsf::is integer $uid] ? " or e.activity_id = :uid" : ""}]
         #
         # - we could pass-in a calendar-clause, would save a query in
         #   the PUT case
Index: openacs-4/packages/xotcl-request-monitor/tcl/throttle_mod-procs.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/xotcl-request-monitor/tcl/throttle_mod-procs.tcl,v
diff -u -r1.67.2.53 -r1.67.2.54
--- openacs-4/packages/xotcl-request-monitor/tcl/throttle_mod-procs.tcl	24 Nov 2022 19:26:45 -0000	1.67.2.53
+++ openacs-4/packages/xotcl-request-monitor/tcl/throttle_mod-procs.tcl	22 Dec 2022 02:51:37 -0000	1.67.2.54
@@ -2049,7 +2049,7 @@
 
   ad_proc -private request_monitor_user_info {key} {
   } {
-    if {[string is integer $key]} {
+    if {[nsf::is integer $key]} {
       #
       # It looks like a user_id
       #
Index: openacs-4/packages/xotcl-request-monitor/www/last-requests.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/xotcl-request-monitor/www/last-requests.tcl,v
diff -u -r1.11.2.6 -r1.11.2.7
--- openacs-4/packages/xotcl-request-monitor/www/last-requests.tcl	25 Mar 2022 20:24:55 -0000	1.11.2.6
+++ openacs-4/packages/xotcl-request-monitor/www/last-requests.tcl	22 Dec 2022 02:51:37 -0000	1.11.2.7
@@ -17,7 +17,7 @@
 set context [list "Last Requests"]
 set hide_patterns [parameter::get -parameter hide-requests -default {*.css}]
 
-if {[string is integer $request_key]} {
+if {[nsf::is integer $request_key]} {
   set user_info   [xo::request_monitor_user_info $request_key]
   set user_string [dict get $user_info label]
   set tmp_url     [dict get $user_info url]
Index: openacs-4/packages/xotcl-request-monitor/www/running.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/xotcl-request-monitor/www/running.tcl,v
diff -u -r1.10.2.4 -r1.10.2.5
--- openacs-4/packages/xotcl-request-monitor/www/running.tcl	6 Apr 2020 17:16:59 -0000	1.10.2.4
+++ openacs-4/packages/xotcl-request-monitor/www/running.tcl	22 Dec 2022 02:51:37 -0000	1.10.2.5
@@ -89,7 +89,7 @@
     set percentage [expr {$done*100.0/$size}]
     set progress [format {%5.2f%% of %5.2f MB} $percentage [expr {$size/1000000.0}]]
     set ms [format %.2f [expr {([clock milliseconds] - $starttime*1000)/-1000.0}]]
-    if {[string is integer $requestor]} {
+    if {[nsf::is integer $requestor]} {
       set user_string [person::name -person_id $requestor]
     } else {
       set user_string $requestor
Index: openacs-4/packages/xotcl-request-monitor/www/whos-online.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/xotcl-request-monitor/www/whos-online.tcl,v
diff -u -r1.16.2.6 -r1.16.2.7
--- openacs-4/packages/xotcl-request-monitor/www/whos-online.tcl	30 Oct 2022 12:13:52 -0000	1.16.2.6
+++ openacs-4/packages/xotcl-request-monitor/www/whos-online.tcl	22 Dec 2022 02:51:37 -0000	1.16.2.7
@@ -68,7 +68,7 @@
   set user_info [xo::request_monitor_user_info $user_id]
   set user_label [dict get $user_info label]
   set user_url   [dict get $user_info url]
-  if {![string is integer $user_id] && $all} {
+  if {![nsf::is integer $user_id] && $all} {
     # it was an IP address
     continue
   }
Index: openacs-4/packages/xowiki/tcl/form-field-procs.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/xowiki/tcl/form-field-procs.tcl,v
diff -u -r1.284.2.231 -r1.284.2.232
--- openacs-4/packages/xowiki/tcl/form-field-procs.tcl	15 Dec 2022 13:17:42 -0000	1.284.2.231
+++ openacs-4/packages/xowiki/tcl/form-field-procs.tcl	22 Dec 2022 02:51:37 -0000	1.284.2.232
@@ -6190,7 +6190,9 @@
     }
     # Validation happens after the value is retrieved.
     # To avoid errors in "clock scan", fix the year if necessary
-    if {![string is integer $year]} {set year 0}
+    if {![nsf::is integer $year]} {
+      set year 0
+    }
 
     foreach v [list year month day hour min sec] {
       if {[set $v] eq ""} {
@@ -6567,7 +6569,7 @@
       # Check, if the calendar_id can be determined
       #
       set calendar_id ""
-      if {[string is integer -strict ${:calendar}]} {
+      if {[nsf::is integer ${:calendar}]} {
         set calendar_id ${:calendar}
         if {[calendar::name $calendar_id] eq ""} {
           set calendar_id ""