diff --git a/etc/postinst.in b/etc/postinst.in
index 37721f575..99443223a 100755
--- a/etc/postinst.in
+++ b/etc/postinst.in
@@ -67,7 +67,7 @@ fi
 
 # This will allow us to install the Perl scripts as executable files
 # without adding the Perl dependencies
-for i in $(find @MAXSCALE_SHAREDIR@/plugins/nagios -name '*.pl')
+for i in $(find @CMAKE_INSTALL_PREFIX@/@MAXSCALE_SHAREDIR@/plugins/nagios -name '*.pl')
 do
     chmod ug+x $i
 done