Index: kmtests/rtl/RtlUnicodeString.c
===================================================================
--- kmtests/rtl/RtlUnicodeString.c	(revision 60823)
+++ kmtests/rtl/RtlUnicodeString.c	(working copy)
@@ -173,7 +173,74 @@
 #endif
 }
 
+static
+VOID
+TestRtlUpcaseUnicodeString(VOID)
+{   
+
+    NTSTATUS Status;
+    LONG Comparison;
+    USHORT i;
+
+    UNICODE_STRING StringUpcased1;
+    UNICODE_STRING StringToUpcase1 = RTL_CONSTANT_STRING(L" rEactOS rO#ks !!\"??");
+    UNICODE_STRING StringUpcasedRef1 = RTL_CONSTANT_STRING(L" REACTOS RO#KS !!\"??");
+
+    UNICODE_STRING StringUpcased2;
+    UNICODE_STRING ZeroLengthString;
+
+    WCHAR MAX[UNICODE_STRING_MAX_BYTES];
+    WCHAR MAXExp[UNICODE_STRING_MAX_BYTES];
+    UNICODE_STRING StringMaxToUpcase;
+    UNICODE_STRING StringMaxUpcased;
+    UNICODE_STRING StringMaxUpcasedExp;
+
+    WCHAR Buffer[10];
+    UNICODE_STRING StringZeroed;
+    UNICODE_STRING StringToUpcase2 = RTL_CONSTANT_STRING(L"aBcde");
+    UNICODE_STRING StringUpcasedRef2  = RTL_CONSTANT_STRING(L"ABCDE0");
+
+
+//  TEST#1: Allocate buffer.
+    RtlUpcaseUnicodeString(&StringUpcased1, &StringToUpcase1, TRUE);
+
+    Comparison = RtlCompareUnicodeString(&StringUpcasedRef1, &StringUpcased1, FALSE);
+    RtlFreeUnicodeString(&StringUpcased1);
+    ok_eq_ulong(Comparison, 0);
+
+//  TEST#2: Allocate Buffer. RtlUpcaseUnicodeString accepts NULL as StringToUpcase argument.
+    RtlInitUnicodeString(&ZeroLengthString, NULL);
+    Status = RtlUpcaseUnicodeString(&StringUpcased2, &ZeroLengthString, TRUE);
+    ok_eq_hex(Status, STATUS_SUCCESS);
+    RtlFreeUnicodeString(&StringUpcased2);
+    ok(StringUpcased2.Buffer == NULL, "Expected NULL" );
+
+//  TEST#3: Allocate UNICODE_STRING_MAX_BYTES buffer
+    for (i = 0; i < (UNICODE_STRING_MAX_BYTES)/sizeof(WCHAR)-1; i++) MAX[i] = L'r';
+    for (i = 0; i < (UNICODE_STRING_MAX_BYTES)/sizeof(WCHAR)-1; i++) MAXExp[i]= L'R';
+
+    RtlInitUnicodeString(&StringMaxToUpcase, MAX);
+    RtlInitUnicodeString(&StringMaxUpcasedExp, MAXExp);
+
+    RtlUpcaseUnicodeString(&StringMaxUpcased, &StringMaxToUpcase, TRUE);
+    
+    Comparison = RtlCompareUnicodeString(&StringMaxUpcased, &StringMaxUpcasedExp, FALSE);
+    RtlFreeUnicodeString(&StringMaxUpcased);
+    ok_eq_ulong(Comparison, 0);
+
+
+//  TEST#4: Don't allocate buffer. Also RtlUpcaseUnicodeString doesnt NULL terminate the StringUpcased
+    RtlInitEmptyUnicodeString(&StringZeroed, Buffer, sizeof(Buffer));
+    RtlAppendUnicodeToString(&StringZeroed, L"000000");
+
+    RtlUpcaseUnicodeString(&StringZeroed, &StringToUpcase2, FALSE);
+    RtlCompareUnicodeString(&StringZeroed, &StringUpcasedRef2, FALSE);
+    ok_eq_wstr(StringZeroed.Buffer, StringUpcasedRef2.Buffer);
+
+}
+
 START_TEST(RtlUnicodeString)
 {
     TestFindCharInUnicodeString();
+    TestRtlUpcaseUnicodeString();
 }