diff --git a/dev/etherpkt.cc b/dev/etherpkt.cc
index 5dee7dc0d..44dbd7c18 100644
--- a/dev/etherpkt.cc
+++ b/dev/etherpkt.cc
@@ -38,6 +38,7 @@ void
 PacketData::serialize(const string &base, ostream &os)
 {
     paramOut(os, base + ".length", length);
+    paramOut(os, base + ".slack", slack);
     arrayParamOut(os, base + ".data", data, length);
 }
 
@@ -46,6 +47,7 @@ PacketData::unserialize(const string &base, Checkpoint *cp,
                         const string &section)
 {
     paramIn(cp, section, base + ".length", length);
+    paramIn(cp, section, base + ".slack", slack);
     if (length)
         arrayParamIn(cp, section, base + ".data", data, length);
 }
diff --git a/dev/etherpkt.hh b/dev/etherpkt.hh
index 82d22bfad..cb9022d72 100644
--- a/dev/etherpkt.hh
+++ b/dev/etherpkt.hh
@@ -47,14 +47,30 @@ class Checkpoint;
 class PacketData : public RefCounted
 {
   public:
+    /*
+     * Pointer to packet data will be deleted
+     */
     uint8_t *data;
+
+    /*
+     * Length of the current packet
+     */
     int length;
 
+    /*
+     * Extra space taken up by the packet in whatever data structure
+     * it is in.
+     *
+     * NOTE: This can only be use by *one* data structure at a time!
+     */
+    int slack;
+
   public:
-    PacketData() : data(NULL), length(0) { }
-    explicit PacketData(size_t size) : data(new uint8_t[size]), length(0) { }
-    PacketData(std::auto_ptr<uint8_t> d, int l)
-        : data(d.release()), length(l) { }
+    PacketData() : data(NULL), length(0), slack(0) { }
+    explicit PacketData(size_t size)
+        : data(new uint8_t[size]), length(0), slack(0) { }
+    PacketData(std::auto_ptr<uint8_t> d, int l, int s = 0)
+        : data(d.release()), length(l), slack(s) { }
     ~PacketData() { if (data) delete [] data; }
 
   public:
diff --git a/dev/pktfifo.hh b/dev/pktfifo.hh
index a8b626618..61e4ead1b 100644
--- a/dev/pktfifo.hh
+++ b/dev/pktfifo.hh
@@ -39,6 +39,10 @@
 class Checkpoint;
 class PacketFifo
 {
+  public:
+    typedef std::list<PacketPtr> fifo_list;
+    typedef fifo_list::iterator iterator;
+
   protected:
     std::list<PacketPtr> fifo;
     int _maxsize;
@@ -64,9 +68,16 @@ class PacketFifo
         return _reserved;
     }
 
+    iterator begin() { return fifo.begin(); }
+    iterator end() { return fifo.end(); }
+
+    PacketPtr front() { return fifo.front(); }
+
     bool push(PacketPtr ptr)
     {
+        assert(ptr->length);
         assert(_reserved <= ptr->length);
+        assert(ptr->slack == 0);
         if (avail() < ptr->length - _reserved)
             return false;
 
@@ -76,25 +87,44 @@ class PacketFifo
         return true;
     }
 
-    PacketPtr front() { return fifo.front(); }
-
     void pop()
     {
         if (empty())
             return;
 
-        _size -= fifo.front()->length;
-        fifo.front() = NULL;
+        PacketPtr &packet = fifo.front();
+        _size -= packet->length;
+        _size -= packet->slack;
+        packet->slack = 0;
+        packet = NULL;
         fifo.pop_front();
     }
 
     void clear()
     {
+        for (iterator i = begin(); i != end(); ++i)
+            (*i)->slack = 0;
         fifo.clear();
         _size = 0;
         _reserved = 0;
     }
 
+    void remove(iterator i)
+    {
+        PacketPtr &packet = *i;
+        if (i != fifo.begin()) {
+            --i;
+            (*i)->slack += packet->length;
+        } else {
+            _size -= packet->length;
+            _size -= packet->slack;
+        }
+
+        packet->slack = 0;
+        packet = NULL;
+        fifo.erase(i);
+    }
+
 /**
  * Serialization stuff
  */