diff --git a/envconf.go b/envconf.go
index d225e53..6b101d9 100644
--- a/envconf.go
+++ b/envconf.go
@@ -60,11 +60,11 @@ func (c *Config) DefineDefault(key string, val string, dtype DataType) {
     entry, ok := c.env[upper]
     if ok {
         if entry.unset {
-            entry.empty = false
             entry.value = val
-            entry.dtype = dtype
-            c.env[upper] = entry
         }
+        entry.dtype = dtype
+        entry.empty = false
+        c.env[upper] = entry
     } else {
         var entry cEntry
         entry.dtype = dtype