Index: /trunk/src/VBox/Frontends/VirtualBox/src/globals/UIIconPool.cpp
===================================================================
--- /trunk/src/VBox/Frontends/VirtualBox/src/globals/UIIconPool.cpp	(revision 70229)
+++ /trunk/src/VBox/Frontends/VirtualBox/src/globals/UIIconPool.cpp	(revision 70230)
@@ -278,4 +278,5 @@
     m_guestOSTypeIconNames.insert("Windows98",       ":/os_win98.png");
     m_guestOSTypeIconNames.insert("WindowsMe",       ":/os_winme.png");
+    m_guestOSTypeIconNames.insert("WindowsNT3x",     ":/os_winnt4.png");
     m_guestOSTypeIconNames.insert("WindowsNT4",      ":/os_winnt4.png");
     m_guestOSTypeIconNames.insert("Windows2000",     ":/os_win2k.png");
Index: /trunk/src/VBox/Frontends/VirtualBox/src/wizards/newvm/UIWizardNewVMPageBasic1.cpp
===================================================================
--- /trunk/src/VBox/Frontends/VirtualBox/src/wizards/newvm/UIWizardNewVMPageBasic1.cpp	(revision 70229)
+++ /trunk/src/VBox/Frontends/VirtualBox/src/wizards/newvm/UIWizardNewVMPageBasic1.cpp	(revision 70230)
@@ -57,5 +57,6 @@
     { QRegExp(  "Wi.*95",                         Qt::CaseInsensitive), "Windows95" },
     { QRegExp(  "Wi.*Me",                         Qt::CaseInsensitive), "WindowsMe" },
-    { QRegExp( "(Wi.*NT)|(NT4)",                  Qt::CaseInsensitive), "WindowsNT4" },
+    { QRegExp( "(Wi.*NT)|(NT[-._v]*4)",           Qt::CaseInsensitive), "WindowsNT4" },
+    { QRegExp( "NT[-._v]*3[.,]*[51x]",            Qt::CaseInsensitive), "WindowsNT3x" },
     /* Note: Do not automatically set WindowsXP_64 on 64-bit hosts, as Windows XP 64-bit
      *       is extremely rare -- most users never heard of it even. So always default to 32-bit. */