diff --git a/lib/request/inject.py b/lib/request/inject.py
index d1d97fd19..a3a8c23b2 100644
--- a/lib/request/inject.py
+++ b/lib/request/inject.py
@@ -468,6 +468,8 @@ def getValue(expression, blind=True, inband=True, error=True, time=True, fromUse
         if isinstance(value, basestring):
             if value.lower() in ("true", "false"):
                 value = bool(value)
+            elif value.capitalize() == "None":
+                value = None
             else:
                 value = value != "0"
         elif isinstance(value, int):
diff --git a/plugins/dbms/maxdb/fingerprint.py b/plugins/dbms/maxdb/fingerprint.py
index 6a62b9856..941d7d600 100644
--- a/plugins/dbms/maxdb/fingerprint.py
+++ b/plugins/dbms/maxdb/fingerprint.py
@@ -134,8 +134,6 @@ class Fingerprint(GenericFingerprint):
             if not conf.extensiveFp:
                 return True
 
-            kb.dbmsVersion = None
-
             return True
         else:
             warnMsg = "the back-end DBMS is not SAP MaxDB"
diff --git a/plugins/dbms/mssqlserver/fingerprint.py b/plugins/dbms/mssqlserver/fingerprint.py
index 572b41f62..19635a3e4 100644
--- a/plugins/dbms/mssqlserver/fingerprint.py
+++ b/plugins/dbms/mssqlserver/fingerprint.py
@@ -132,6 +132,16 @@ class Fingerprint(GenericFingerprint):
 
                         break
 
+            if not kb.dbmsVersion or kb.dbmsVersion == ["Unknown"]:
+                for version, check in [\
+                        ("2000", "HOST_NAME()=HOST_NAME()"),\
+                        ("2005", "XACT_STATE()=XACT_STATE()"),\
+                        ("2008", "SYSDATETIME()>0") ]:
+                    result = inject.checkBooleanExpression(check)
+
+                    if result:
+                        kb.dbmsVersion = [version]
+
             if kb.dbmsVersion:
                 setDbms("%s %s" % (DBMS.MSSQL, kb.dbmsVersion[0]))
             else: