diff --git a/ip.py b/ip.py
index 6641a23..c6f3b81 100755
--- a/ip.py
+++ b/ip.py
@@ -494,7 +494,7 @@ class Session:
 
         saddr = chunk.first.saddr
         try:
-            (first, data) = self.pending.pop(saddr)
+            (first, data) = self.pending[saddr]
         except KeyError:
             first = chunk.first
             data = gapstr.GapString()