diff -Nru firebird3.0-3.0.7.33374.ds4/debian/changelog firebird3.0-3.0.7.33374.ds4/debian/changelog
--- firebird3.0-3.0.7.33374.ds4/debian/changelog	2020-10-20 17:07:16.000000000 +0000
+++ firebird3.0-3.0.7.33374.ds4/debian/changelog	2020-12-25 20:12:41.000000000 +0000
@@ -1,3 +1,10 @@
+firebird3.0 (3.0.7.33374.ds4-2) unstable; urgency=medium
+
+  * work around problems with Turkish locale during configuration
+    (Closes: #978074)
+
+ -- Damyan Ivanov <dmn@debian.org>  Fri, 25 Dec 2020 20:12:41 +0000
+
 firebird3.0 (3.0.7.33374.ds4-1) unstable; urgency=medium
 
   * Use secure URI for Homepage.
diff -Nru firebird3.0-3.0.7.33374.ds4/debian/functions.sh firebird3.0-3.0.7.33374.ds4/debian/functions.sh
--- firebird3.0-3.0.7.33374.ds4/debian/functions.sh	2020-10-20 16:57:35.000000000 +0000
+++ firebird3.0-3.0.7.33374.ds4/debian/functions.sh	2020-12-25 15:10:53.000000000 +0000
@@ -138,9 +138,13 @@
         trap "rm -rf '$T'" 0 INT QUIT
         local T_SEC="$T/security.fdb"
 
-        echo "create database '$T_SEC';" | isql-fb -q
-        gfix -user SYSDBA -write async "$T_SEC"
-        isql-fb -user SYSDBA -i "$SEC_SQL" "$T_SEC"
+        (
+            set -e
+            export LANG=C
+            echo "create database '$T_SEC';" | isql-fb -q
+            gfix -user SYSDBA -write async "$T_SEC"
+            isql-fb -user SYSDBA -i "$SEC_SQL" "$T_SEC"
+        )
         gfix -user SYSDBA -write sync "$T_SEC"
         install -o firebird -g firebird -m 0660 "$T_SEC" "$SEC_DB"