diff --git a/meta-digi-dey/classes/trustfence.bbclass b/meta-digi-dey/classes/trustfence.bbclass
index 0e734044a..8bacd48a3 100644
--- a/meta-digi-dey/classes/trustfence.bbclass
+++ b/meta-digi-dey/classes/trustfence.bbclass
@@ -60,6 +60,6 @@ python () {
             d.appendVar("UBOOT_EXTRA_CONF", "CONFIG_ENCRYPT_IMAGE=y ")
             if d.getVar("TRUSTFENCE_UBOOT_DEK_SIZE", True):
                 d.appendVar("UBOOT_EXTRA_CONF", "CONFIG_DEK_SIZE=%s " % d.getVar("TRUSTFENCE_UBOOT_DEK_SIZE"))
-    if d.getVar("TRUSTFENCE_UBOOT_ENV_DEK", True):
+    if (d.getVar("TRUSTFENCE_UBOOT_ENV_DEK", True) not in [None, "0"]):
         d.appendVar("UBOOT_EXTRA_CONF", 'CONFIG_ENV_AES=y CONFIG_ENV_AES_KEY=\\"%s\\"' % d.getVar("TRUSTFENCE_UBOOT_ENV_DEK"))
 }