diff --git a/build.gradle b/build.gradle
index 6f984c16..65e6f777 100644
--- a/build.gradle
+++ b/build.gradle
@@ -64,7 +64,7 @@ javadocJar.enabled = false
 ext {
     slf4jVersion = '1.7.7'
     servletApiVersion = '3.1.0'
-    zipkinVersion = '1.8.4'
+    zipkinVersion = '1.11.1'
 
     junitVersion = '4.11'
     mockitoVersion = '1.9.5'
diff --git a/wingtips-core/src/main/java/com/nike/wingtips/TraceAndSpanIdGenerator.java b/wingtips-core/src/main/java/com/nike/wingtips/TraceAndSpanIdGenerator.java
index 1b5cc291..7810f3d8 100644
--- a/wingtips-core/src/main/java/com/nike/wingtips/TraceAndSpanIdGenerator.java
+++ b/wingtips-core/src/main/java/com/nike/wingtips/TraceAndSpanIdGenerator.java
@@ -116,8 +116,8 @@ protected static Random getRandomInstance(String desiredSecureRandomImplementati
 
     /**
      * <p>
-     *     The code in this class came from the Zipkin repository v1.7.0
-     *     (https://github.com/openzipkin/zipkin/blob/master/zipkin/src/main/java/zipkin/internal/Util.java)
+     *     The code in this class came from the Zipkin repository v1.11.1
+     *     (https://github.com/openzipkin/zipkin/blob/1.11.1/zipkin/src/main/java/zipkin/internal/Util.java)
      *     and licensed under the Apache License, Version 2.0 (http://www.apache.org/licenses/LICENSE-2.0).
      * </p>
      */
@@ -127,14 +127,20 @@ private ZipkinHexHelpers() {
             // Do nothing
         }
 
-        /** Parses a 1 to 16 character lower-hex string with no prefix int an unsigned long. */
-        static long lowerHexToUnsignedLong(String lowerHex) {
-            char[] array = lowerHex.toCharArray();
-            if (array.length < 1 || array.length > 16) {
-                throw isntLowerHexLong(lowerHex);
-            }
+        /**
+         * Parses a 1 to 32 character lower-hex string with no prefix into an unsigned long, tossing any
+         * bits higher than 64.
+         */
+        public static long lowerHexToUnsignedLong(String lowerHex) {
+            int length = lowerHex.length();
+            if (length < 1 || length > 32) throw isntLowerHexLong(lowerHex);
+
+            // trim off any high bits
+            int i = length > 16 ? length - 16 : 0;
+
             long result = 0;
-            for (char c : array) {
+            for (; i < length; i++) {
+                char c = lowerHex.charAt(i);
                 result <<= 4;
                 if (c >= '0' && c <= '9') {
                     result |= c - '0';
@@ -149,7 +155,7 @@ static long lowerHexToUnsignedLong(String lowerHex) {
 
         static NumberFormatException isntLowerHexLong(String lowerHex) {
             return new NumberFormatException(
-                lowerHex + " should be a 1 to 16 character lower-hex string with no prefix");
+                lowerHex + " should be a 1 to 32 character lower-hex string with no prefix");
         }
 
         /** Inspired by {@code okio.Buffer.writeLong} */
diff --git a/wingtips-core/src/test/java/com/nike/wingtips/TraceAndSpanIdGeneratorTest.java b/wingtips-core/src/test/java/com/nike/wingtips/TraceAndSpanIdGeneratorTest.java
index b50da952..ef08a5a7 100644
--- a/wingtips-core/src/test/java/com/nike/wingtips/TraceAndSpanIdGeneratorTest.java
+++ b/wingtips-core/src/test/java/com/nike/wingtips/TraceAndSpanIdGeneratorTest.java
@@ -230,13 +230,13 @@ public void longToUnsignedLowerHexString_and_unsignedLowerHexStringToLong_work_a
     }
 
     @DataProvider(value = {
-        "                   ", // less than 16 chars
-        "12345678901234567  ", // longer than 16 chars
-        "/                  ", // before '0' char
-        ":                  ", // after '9' char
-        "`                  ", // before 'a' char
-        "g                  ", // after 'f' char
-        "ABCDEF             "  // uppercase hex chars
+        "                                      ", // less than 16 chars
+        "123e4567-e89b-12d3-a456-426655440000  ", // longer than 32 chars
+        "/                                     ", // before '0' char
+        ":                                     ", // after '9' char
+        "`                                     ", // before 'a' char
+        "g                                     ", // after 'f' char
+        "ABCDEF                                "  // uppercase hex chars
     }, splitBy = "\\|")
     @Test
     public void unsignedLowerHexStringToLong_throws_NumberFormatException_for_illegal_args(final String badHexString) {
diff --git a/wingtips-zipkin/src/test/java/com/nike/wingtips/zipkin/util/WingtipsToZipkinSpanConverterDefaultImplTest.java b/wingtips-zipkin/src/test/java/com/nike/wingtips/zipkin/util/WingtipsToZipkinSpanConverterDefaultImplTest.java
index 483e89e3..8598d252 100644
--- a/wingtips-zipkin/src/test/java/com/nike/wingtips/zipkin/util/WingtipsToZipkinSpanConverterDefaultImplTest.java
+++ b/wingtips-zipkin/src/test/java/com/nike/wingtips/zipkin/util/WingtipsToZipkinSpanConverterDefaultImplTest.java
@@ -135,4 +135,25 @@ public void convertWingtipsSpanToZipkinSpan_works_as_expected_for_all_nullable_i
         verifySpanPurposeRelatedStuff(zipkinSpan, wingtipsSpan, zipkinEndpoint, localComponentNamespace);
     }
 
-}
\ No newline at end of file
+    @Test
+    public void convertWingtipsSpanToZipkinSpan_works_as_expected_for_128_bit_trace_id() {
+        // given
+        String hex128Bits = "463ac35c9f6413ad48485a3953bb6124";
+        String lower64Bits = "48485a3953bb6124";
+
+        String spanName = UUID.randomUUID().toString();
+        String traceId = hex128Bits;
+        String spanId = lower64Bits;
+        long startTimeEpochMicros = Math.abs(random.nextLong());
+        long durationNanos = Math.abs(random.nextLong());
+        Endpoint zipkinEndpoint = Endpoint.create(UUID.randomUUID().toString(), 42);
+        String localComponentNamespace = UUID.randomUUID().toString();
+        Span wingtipsSpan = new Span(traceId, null, spanId, spanName, true, null, Span.SpanPurpose.CLIENT, startTimeEpochMicros, null, durationNanos);
+
+        // when
+        zipkin.Span zipkinSpan = impl.convertWingtipsSpanToZipkinSpan(wingtipsSpan, zipkinEndpoint, localComponentNamespace);
+
+        // then
+        assertThat(zipkinSpan.traceId).isEqualTo(unsignedLowerHexStringToLong(lower64Bits));
+    }
+}