diff --git a/dlls/ntdll/nt.c b/dlls/ntdll/nt.c
index 228dc1218c6..24309dbf452 100644
--- a/dlls/ntdll/nt.c
+++ b/dlls/ntdll/nt.c
@@ -737,3 +737,13 @@ NTSTATUS WINAPI NtAllocateLocallyUniqueId(PLUID Luid)
 
     return STATUS_SUCCESS;
 }
+
+/******************************************************************************
+ *        VerSetConditionMask   (NTDLL.@)
+ */
+ULONGLONG WINAPI VerSetConditionMask( ULONGLONG dwlConditionMask, DWORD dwTypeBitMask,
+                                      BYTE dwConditionMask)
+{
+    FIXME("%llx %lu %u\n", dwlConditionMask, dwTypeBitMask, dwConditionMask);
+    return dwlConditionMask;
+}
diff --git a/dlls/ntdll/ntdll.spec b/dlls/ntdll/ntdll.spec
index 2914d24674f..77b509f16b4 100644
--- a/dlls/ntdll/ntdll.spec
+++ b/dlls/ntdll/ntdll.spec
@@ -310,7 +310,7 @@ debug_channels (atom cdrom console debug delayhlp dll dosfs dosmem file fixup
 @ stub RtlConvertExclusiveToShared
 @ stdcall -ret64 RtlConvertLongToLargeInteger(long) RtlConvertLongToLargeInteger
 @ stub RtlConvertSharedToExclusive
-@ stdcall RtlConvertSidToUnicodeString(ptr ptr)RtlConvertSidToUnicodeString
+@ stdcall RtlConvertSidToUnicodeString(ptr ptr long) RtlConvertSidToUnicodeString
 @ stub RtlConvertUiListToApiList
 @ stdcall -ret64 RtlConvertUlongToLargeInteger(long) RtlConvertUlongToLargeInteger
 @ stub RtlCopyLuid
@@ -1013,6 +1013,7 @@ debug_channels (atom cdrom console debug delayhlp dll dosfs dosmem file fixup
 @ stub RtlCreatePropertySet
 @ stub RtlSetPropertySetClassId
 @ stdcall NtPowerInformation(long long long long long) NtPowerInformation
+@ stdcall -ret64 VerSetConditionMask(long long long long) VerSetConditionMask
 
 ##################
 # Wine extensions
diff --git a/dlls/ntdll/sec.c b/dlls/ntdll/sec.c
index 37c79a15f61..2d026b5dc66 100644
--- a/dlls/ntdll/sec.c
+++ b/dlls/ntdll/sec.c
@@ -23,6 +23,9 @@
 #include <time.h>
 #include <ctype.h>
 #include <math.h>
+#include <pwd.h>
+#include <unistd.h>
+
 #include "windef.h"
 #include "winbase.h"
 #include "wine/exception.h"
@@ -721,23 +724,29 @@ NTSTATUS WINAPI RtlGetControlSecurityDescriptor(
 
 /******************************************************************************
  * RtlConvertSidToUnicodeString (NTDLL.@)
+ *
+ * The returned SID is used to access the USER registry hive usually
+ *
+ * the native function returns something like
+ * "S-1-5-21-0000000000-000000000-0000000000-500";
  */
 NTSTATUS WINAPI RtlConvertSidToUnicodeString(
-       PUNICODE_STRING UnicodeSID,
-       PSID *pSid)
+       PUNICODE_STRING String,
+       PSID Sid,
+       BOOLEAN AllocateString)
 {
-/*	LPSTR GenSID = "S-1-5-21-0000000000-000000000-0000000000-500"; */
-
-	LPSTR GenSID = ".Default";	/* usually the returned SID is used to */
-					/* access  "\\REGISTRY\\USER\\.DEFAULT" */
-
+        const char *p;
+        NTSTATUS status;
         ANSI_STRING AnsiStr;
 
-	FIXME("(%p %p)\n", UnicodeSID, pSid);
-        if (UnicodeSID)
-            TRACE("%p(<OUT>) (%u %u)\n",
-                  UnicodeSID->Buffer, UnicodeSID->Length, UnicodeSID->MaximumLength);
+        struct passwd *pwd = getpwuid( getuid() );
+        p = (pwd) ? pwd->pw_name : ".Default";
 
-        RtlInitAnsiString(&AnsiStr, GenSID);
-        return RtlAnsiStringToUnicodeString(UnicodeSID, &AnsiStr, TRUE);
+	FIXME("(%p %p %u)\n", String, Sid, AllocateString);
+
+        RtlInitAnsiString(&AnsiStr, p);
+        status = RtlAnsiStringToUnicodeString(String, &AnsiStr, AllocateString);
+
+        TRACE("%s (%u %u)\n",debugstr_w(String->Buffer),String->Length,String->MaximumLength);
+        return status;
 }