diff --git a/scapy/fields.py b/scapy/fields.py
index ad9c9a76af9e430b1c4f1e08b57a1b96dfd6b0b5..4d05feb9c8e1de23490cd345243000429f8d2175 100644
--- a/scapy/fields.py
+++ b/scapy/fields.py
@@ -418,7 +418,7 @@ class PacketListField(PacketField):
         if x is None:
             return None
         else:
-            return map(lambda p:p.copy(), x)
+            return [p if isinstance(p, basestring) else p.copy() for p in x]
     def getfield(self, pkt, s):
         c = l = None
         if self.length_from is not None: