diff --git a/src/lib/idi/entry-id.hpp b/src/lib/idi/entry-id.hpp
index 4579fc438..f11c0d5dc 100644
--- a/src/lib/idi/entry-id.hpp
+++ b/src/lib/idi/entry-id.hpp
@@ -113,7 +113,8 @@ namespace idi {
       size_t l = sym.length();
       if (l > 1) boost::hash_combine(seed, KNUTH_MAGIC * sym[l-1]);
       if (l > 2) boost::hash_combine(seed, KNUTH_MAGIC * sym[l-2]);
-      if (l > 3) boost::hash_combine(seed, KNUTH_MAGIC * sym[l-3]);       ////////////////////////TICKET #865
+      if (l > 3) boost::hash_combine(seed, KNUTH_MAGIC * sym[l-3]);
+      if (l > 4) boost::hash_combine(seed, KNUTH_MAGIC * sym[l-4]);       ////////////////////////TICKET #865
       
       boost::hash_combine(seed, sym);
       lumiera_uid tmpLUID;
diff --git a/tests/library/hash-generator-test.cpp b/tests/library/hash-generator-test.cpp
index 930c60824..4a494c094 100644
--- a/tests/library/hash-generator-test.cpp
+++ b/tests/library/hash-generator-test.cpp
@@ -114,8 +114,10 @@ namespace test{
        * bonus points if this number is also a prime. An additional factor of 2 does not hurt
        * (so in case of 64bit platform).
        * 
-       * In our case, it is sufficient to apply this trick to the trailing two digits;
+       * In our case, it is sufficient to apply this trick to the trailing four digits;
        * without this trick, we get the first collisions after about 20000 running numbers.
+       * @note on x86_64, even just spreading the trailing two digits seem to be sufficient
+       *      to remove any collisions from the first 100000 numbers.
        * @see BareEntryID
        */
       void
@@ -128,7 +130,7 @@ namespace test{
           const size_t KNUTH_MAGIC = 2654435761;
           
           uint collisions(0);
-          for (uint i=0; i<100000; ++i)
+          for (uint i=0; i<20000; ++i)
             {
               string candidate = prefix + lexical_cast<string> (i);
               size_t l = candidate.length();
@@ -136,6 +138,8 @@ namespace test{
               
               boost::hash_combine(hashVal, KNUTH_MAGIC * candidate[l-1]);
               boost::hash_combine(hashVal, KNUTH_MAGIC * candidate[l-2]);
+              boost::hash_combine(hashVal, KNUTH_MAGIC * candidate[l-3]);
+              boost::hash_combine(hashVal, KNUTH_MAGIC * candidate[l-4]);
               boost::hash_combine(hashVal, candidate);
               
               if (contains (hashValues, hashVal))