Index: openacs-4/packages/categories/www/cadmin/category-link-add-2.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/categories/www/cadmin/category-link-add-2.tcl,v
diff -u -r1.7.4.1 -r1.7.4.2
--- openacs-4/packages/categories/www/cadmin/category-link-add-2.tcl	29 Sep 2013 12:04:42 -0000	1.7.4.1
+++ openacs-4/packages/categories/www/cadmin/category-link-add-2.tcl	3 Oct 2013 07:56:58 -0000	1.7.4.2
@@ -53,7 +53,7 @@
     set backward_exists_p [info exists backward_links($link_category_id)]
 
     template::multirow append tree $link_category_name $link_category_id $forward_exists_p $backward_exists_p \
-	[string repeat " " [expr ($level-1)*5]] \
+	[string repeat " " [expr {($level-1)*5]}] \
 	[export_vars -no_empty -base category-links-view {{category_id $link_category_id} {tree_id $link_tree_id} locale object_id  ctx_id}] \
 	[export_vars -no_empty -base category-link-add-3 {link_category_id category_id tree_id locale object_id ctx_id}] \
 	[export_vars -no_empty -base category-link-add-4 {link_category_id category_id tree_id locale object_id ctx_id}]