Index: /trunk/src/VBox/Runtime/common/misc/cidr.cpp
===================================================================
--- /trunk/src/VBox/Runtime/common/misc/cidr.cpp	(revision 29836)
+++ /trunk/src/VBox/Runtime/common/misc/cidr.cpp	(revision 29837)
@@ -55,5 +55,5 @@
     *(uint32_t *)addr = 0;
     if (pszNetmask == NULL)
-        cBits = 0; 
+        cBits = 32; 
     else 
     { 
@@ -72,7 +72,7 @@
     if (cBits < 9)
         cDelimiterLimit = 0;
-    else if (cBits < 16)
+    else if (cBits <= 16)
         cDelimiterLimit = 1;
-    else if (cBits < 25)
+    else if (cBits <= 24)
         cDelimiterLimit = 2;
     else if (cBits <= 32)
@@ -84,5 +84,7 @@
         if (*pszNext == '.')
             cDelimiter++;
-        else if(cDelimiter >= cDelimiterLimit)
+        else if(   cDelimiter >= cDelimiterLimit
+                && (   *pszNext == '\0'
+                    || *pszNext == '/'))
             break;
         else 
Index: /trunk/src/VBox/Runtime/testcase/tstRTCidr.cpp
===================================================================
--- /trunk/src/VBox/Runtime/testcase/tstRTCidr.cpp	(revision 29836)
+++ /trunk/src/VBox/Runtime/testcase/tstRTCidr.cpp	(revision 29837)
@@ -86,6 +86,6 @@
     /* RFC 4632 s3.1: legacy "Class B" is n.n.0.0/16 */
     CHECKNETWORK("10.1.2/16",      VERR_INVALID_PARAMETER,          0,          0);
+    CHECKNETWORK("10.1/16",     VINF_SUCCESS,          0x0A010000,          0xFFFF0000);
     CHECKNETWORK("10.1.0.0/16",              VINF_SUCCESS, 0x0A010000, 0xFFFF0000);
-    CHECKNETWORK("10.1/16",                  VINF_SUCCESS, 0x0A010000, 0xFFFF0000);
     CHECKNETWORK("1.2.3.4",                  VINF_SUCCESS, 0x01020304, 0xFFFFFFFF);
     CHECKNETWORK("1.2.3.255",                VINF_SUCCESS, 0x010203FF, 0xFFFFFFFF);
@@ -95,4 +95,5 @@
     CHECKNETWORK("10.255.1/24",              VINF_SUCCESS, 0x0AFF0100, 0xFFFFFF00);
     CHECKNETWORK("10.255.1.1/24",  VERR_INVALID_PARAMETER,          0,          0);
+    CHECKNETWORK("1.2",            VERR_INVALID_PARAMETER,          0,          0);
 
     return RTTestSummaryAndDestroy(hTest);