diff --git a/pyracf/common/irrsmo00.c b/pyracf/common/irrsmo00.c
index 85c7580..9f3325b 100644
--- a/pyracf/common/irrsmo00.c
+++ b/pyracf/common/irrsmo00.c
@@ -127,10 +127,10 @@ static PyObject *call_irrsmo00(PyObject *self, PyObject *args, PyObject *kwargs)
     // Py_BuildValue() will return a Tuple.
 
     return Py_BuildValue(
-        "{s:y#,s:[B,B,B],s:y}", 
+        "{s:y#,s:[B,B,B],s:y#}", 
         "resultBuffer", result_buffer, result_len,
         "returnCodes", saf_rc, racf_rc, racf_rsn,
-        "handle",request_handle);
+        "handle", request_handle, 64);
 }
 
 static char call_irrsmo00_docs[] =
diff --git a/pyracf/common/irrsmo00.py b/pyracf/common/irrsmo00.py
index b04fd6a..afc3535 100644
--- a/pyracf/common/irrsmo00.py
+++ b/pyracf/common/irrsmo00.py
@@ -86,7 +86,7 @@ def call_racf(
         # Preserve raw result XML just in case we need to create a dump.
         # If the decoded result XML cannot be parsed with the XML parser,
         # a dump may need to be taken to aid in problem determination.
-        self.__raw_result_xml = b"".join(result["resultBuffers"])
+        self.__raw_result_xml = result["resultBuffer"]
         # Replace any null bytes in the result XML with spaces.
         result_xml = self.__null_byte_fix(self.__raw_result_xml)
         # 'irrsmo00.c' returns a raw unmodified bytes object containing a copy
diff --git a/tests/common/test_irrsmo00_interface.py b/tests/common/test_irrsmo00_interface.py
index f0bc307..f1da958 100644
--- a/tests/common/test_irrsmo00_interface.py
+++ b/tests/common/test_irrsmo00_interface.py
@@ -57,7 +57,7 @@ def test_irrsmo00_null_byte_fix(
         ])
         # fmt: on
         call_irrsmo00_wrapper_mock.return_value = {
-            "resultBuffers": [xml_containing_null_bytes],
+            "resultBuffer": xml_containing_null_bytes,
             "returnCodes": [0, 0, 0],
         }
         self.assertEqual(
@@ -71,7 +71,7 @@ def test_irrsmo00_empty_result(
     ):
         # Simulate failure due to incomplete 'IRR.IRRSMO00.PRECHECK' setup
         call_irrsmo00_wrapper_mock.return_value = {
-            "resultBuffers": [bytes([0 for i in range(256)])],
+            "resultBuffer": bytes([0 for i in range(256)]),
             "returnCodes": [8, 200, 16],
         }
         self.assertEqual(self.irrsmo00.call_racf(b""), [8, 200, 16])
@@ -82,7 +82,7 @@ def test_irrsmo00_result_buffer_full_failure(
     ):
         # Simulate scenario where result buffer is too small.
         call_irrsmo00_wrapper_mock.return_value = {
-            "resultBuffers": [self.good_xml[:32]],
+            "resultBuffer": self.good_xml[:32],
             "returnCodes": [8, 4000, 100000000],
         }
         self.assertEqual(
@@ -95,7 +95,7 @@ def test_irrsmo00_result_buffer_full_success(
     ):
         # Simulate scenario where result buffer is exactly the right size.
         call_irrsmo00_wrapper_mock.return_value = {
-            "resultBuffers": [self.good_xml[: self.good_xml_null_terminator_index]],
+            "resultBuffer": self.good_xml[: self.good_xml_null_terminator_index],
             "returnCodes": [0, 0, 0],
         }
         self.assertEqual(
@@ -105,7 +105,7 @@ def test_irrsmo00_result_buffer_full_success(
 
     def test_irrsmo00_normal_result(self, call_irrsmo00_wrapper_mock: Mock):
         call_irrsmo00_wrapper_mock.return_value = {
-            "resultBuffers": [self.good_xml],
+            "resultBuffer": self.good_xml,
             "returnCodes": [0, 0, 0],
         }
         self.assertEqual(
@@ -118,7 +118,7 @@ def test_irrsmo00_normal_result(self, call_irrsmo00_wrapper_mock: Mock):
     # ============================================================================
     def test_irrsmo00_minimum_arguments(self, call_irrsmo00_wrapper_mock: Mock):
         call_irrsmo00_wrapper_mock.return_value = {
-            "resultBuffers": [self.good_xml],
+            "resultBuffer": self.good_xml,
             "returnCodes": [0, 0, 0],
         }
         self.irrsmo00.call_racf(b"some bytes")
@@ -133,7 +133,7 @@ def test_irrsmo00_minimum_arguments(self, call_irrsmo00_wrapper_mock: Mock):
 
     def test_irrsmo00_with_precheck_set_to_true(self, call_irrsmo00_wrapper_mock: Mock):
         call_irrsmo00_wrapper_mock.return_value = {
-            "resultBuffers": [self.good_xml],
+            "resultBuffer": self.good_xml,
             "returnCodes": [0, 0, 0],
         }
         self.irrsmo00.call_racf(b"some bytes", precheck=True)
@@ -148,7 +148,7 @@ def test_irrsmo00_with_precheck_set_to_true(self, call_irrsmo00_wrapper_mock: Mo
 
     def test_irrsmo00_with_run_as_userid_set(self, call_irrsmo00_wrapper_mock: Mock):
         call_irrsmo00_wrapper_mock.return_value = {
-            "resultBuffers": [self.good_xml],
+            "resultBuffer": self.good_xml,
             "returnCodes": [0, 0, 0],
         }
         self.irrsmo00.call_racf(b"some bytes", run_as_userid="KRABS")
@@ -165,7 +165,7 @@ def test_irrsmo00_with_custom_result_buffer_size(
         self, call_irrsmo00_wrapper_mock: Mock
     ):
         call_irrsmo00_wrapper_mock.return_value = {
-            "resultBuffers": [self.good_xml],
+            "resultBuffer": self.good_xml,
             "returnCodes": [0, 0, 0],
         }
         irrsmo00 = IRRSMO00(result_buffer_size=32768)