diff --git a/dkbuild b/dkbuild
index dd09277..48c83dd 100755
--- a/dkbuild
+++ b/dkbuild
@@ -1834,7 +1834,7 @@ function define_functions_cmd() {
             shift
         done
 
-        [ -n "${DEFAULTS[build_build]-1}" ] || return
+        [ -n "${DEFAULTS[build_build]-1}" ] || return 0
         [ -n "$output" ] || die "genfile: Vous devez spécifier le fichier en sortie"
         if [ -n "$context" ]; then
             mkdir -p "$context" || die
@@ -1870,7 +1870,7 @@ function define_functions_cmd() {
             shift
         done
 
-        [ -n "${DEFAULTS[build_build]-1}" ] || return
+        [ -n "${DEFAULTS[build_build]-1}" ] || return 0
         [ -n "$DOCKERFILE" ] || DOCKERFILE=Dockerfile
         DOCKERCONTEXT=.
         if [ -n "$context" ]; then
@@ -1894,7 +1894,7 @@ function define_functions_cmd() {
     function add2dockerfile() {
         edebug "$(qvals "$@")"
 
-        [ -n "${DEFAULTS[build_build]-1}" ] || return
+        [ -n "${DEFAULTS[build_build]-1}" ] || return 0
         [ -n "$DOCKERFILE" ] || return
         echo "$*" >>"$DOCKERFILE"
     }
@@ -2380,7 +2380,7 @@ exit((PHP_VERSION_ID < $version)? 0: 1);
     function _local_mvn() {
         if [ -n "$java" ]; then
             urequire java
-            select_java_exact "$java" || die
+            select_java_exact "$java" || die "mvn: Java $java introuvable"
             export MVN_JAVA_VERSION="$java"
         fi