diff --git a/configomat.sh b/configomat.sh
index 71ba4c3..f651670 100755
--- a/configomat.sh
+++ b/configomat.sh
@@ -9,25 +9,34 @@ configomat_do_work() {
 
 	_env_variable_prefix=$1
 	[ -z ${_env_variable_prefix} ] && \
-  echo "I could not find the env prefix. Exiting ..." && return 1
+    echo "I could not find the env prefix. Exiting ..." && \
+	return 1
 
 	IFS=" " read -r -a _config_files <<< $2
 
+	_tmpf=$(mktemp /tmp/configomat.XXXXXX) || exit 1
+
+	printenv | grep $_env_variable_prefix > $_tmpf
+
 	# dispatch env variables
-	for env_variable in $(printenv | grep $_env_variable_prefix);do
+	# for env_variable in $(printenv | grep $_env_variable_prefix);do
+	while read env_variable
+	do
 		# get key
 		# IFS not working because values like ldap_query_filter or search base consists of several '='
 		# IFS="=" read -r -a __values <<< $env_variable
 		# key="${__values[0]}"
 		# value="${__values[1]}"
-		key=$(echo $env_variable | cut -d "=" -f1)
+		key="$(echo $env_variable | cut -d '=' -f1)"
 		key=${key#"${_env_variable_prefix}"}
 		# make key lowercase
 		key=${key,,}
 		# get value
-		value=$(echo $env_variable | cut -d "=" -f2-)
-		config_overrides[$key]=$value
-	done
+		value="$(echo $env_variable | cut -d '=' -f2-)"
+		config_overrides[$key]="$value"
+	done <$_tmpf
+
+	rm -f $_tmpf
 
 	for f in "${_config_files[@]}"
 	do
@@ -38,10 +47,10 @@ configomat_do_work() {
 			do
 				[ -z $key ] && echo -e "\t no key provided" && return 1
 
-        echo "  >> $f: $key = ${config_overrides[$key]}"
+				echo "  >> $f: $key = ${config_overrides[$key]}"
 
 				# Escape special characters
-				config_overrides[$key]=$((echo ${config_overrides[$key]}|sed -r 's/([\&\|\$\.\*\/\[\\^])/\\\1/g'|sed 's/[]]/\[]]/g')>&1)
+				config_overrides[$key]="$((echo ${config_overrides[$key]}|sed -r 's/([\=\&\|\$\.\*\/\[\\^])/\\\1/g'|sed 's/[]]/\[]]/g')>&1)"
 
 				sed -i -e "s|^${key}[[:space:]]\+.*|${key} = ${config_overrides[$key]}|g" \
 				${f}
diff --git a/test/example.conf b/test/example.conf
index 7029623..771c6b0 100644
--- a/test/example.conf
+++ b/test/example.conf
@@ -4,3 +4,7 @@ key_3 =
 key_4 =value_4
 key_5= value_5
 key_6=value_6
+key_7 = value_7
+key_8 = value_8
+key_9 = value_9
+key_10 = value_10
\ No newline at end of file
diff --git a/test/tests.bats b/test/tests.bats
index 11ecf71..d98b094 100644
--- a/test/tests.bats
+++ b/test/tests.bats
@@ -56,3 +56,37 @@ load 'test_helper/bats-assert/all'
 #   grep 'key_6 = new_value_6' /tmp/example.conf 2>&1 > /dev/null
 #   assert_success
 # }
+
+# #5 Check Problem from docker-mailserver: config_overrides[$key]: bad array subscript
+
+@test "#5 Key Value 1" {
+  export TEST_key_7="uid=user,userPassword=password"
+  ./configomat.sh TEST_ /tmp/example.conf
+  assert_success
+  grep "key_7 = uid=user,userPassword=password" /tmp/example.conf 2>&1 > /dev/null
+  assert_success
+}
+
+@test "#5 Key Value 2" {
+  export "TEST_key_8=(&(objectClass=mailAccount)(uid=%n))"
+  ./configomat.sh TEST_ /tmp/example.conf
+  assert_success
+  grep "key_8 = (&(objectClass=mailAccount)(uid=%n))" /tmp/example.conf 2>&1 > /dev/null
+  assert_success
+}
+
+@test "#5 Key Value 3" {
+  export TEST_key_9="=home=/var/mail/%{ldap:mail}, =mail=maildir:/var/mail/%{ldap:mail}/Maildir"
+  ./configomat.sh TEST_ /tmp/example.conf
+  assert_success
+  grep 'key_9 = =home=/var/mail/%{ldap:mail}, =mail=maildir:/var/mail/%{ldap:mail}/Maildir' /tmp/example.conf 2>&1 > /dev/null
+  assert_success
+}
+
+@test "#5 Key Value 4" {
+  export TEST_key_10="(&(objectClass=mailAccount)(uid=%n))"
+  ./configomat.sh TEST_ /tmp/example.conf
+  assert_success
+  grep 'key_10 = (&(objectClass=mailAccount)(uid=%n))' /tmp/example.conf 2>&1 > /dev/null
+  assert_success
+}