diff --git a/lib/core/settings.py b/lib/core/settings.py
index dfb4e6411..ae57de062 100644
--- a/lib/core/settings.py
+++ b/lib/core/settings.py
@@ -18,7 +18,7 @@ from lib.core.enums import OS
 from thirdparty.six import unichr as _unichr
 
 # sqlmap version (<major>.<minor>.<month>.<monthly commit>)
-VERSION = "1.3.8.31"
+VERSION = "1.3.9.0"
 TYPE = "dev" if VERSION.count('.') > 2 and VERSION.split('.')[-1] != '0' else "stable"
 TYPE_COLORS = {"dev": 33, "stable": 90, "pip": 34}
 VERSION_STRING = "sqlmap/%s#%s" % ('.'.join(VERSION.split('.')[:-1]) if VERSION.count('.') > 2 and VERSION.split('.')[-1] == '0' else VERSION, TYPE)
diff --git a/plugins/dbms/firebird/fingerprint.py b/plugins/dbms/firebird/fingerprint.py
index 055b63c68..79ca5e352 100644
--- a/plugins/dbms/firebird/fingerprint.py
+++ b/plugins/dbms/firebird/fingerprint.py
@@ -10,6 +10,7 @@ import re
 from lib.core.common import Backend
 from lib.core.common import Format
 from lib.core.common import randomRange
+from lib.core.common import randomStr
 from lib.core.compat import xrange
 from lib.core.convert import getUnicode
 from lib.core.data import conf
@@ -74,13 +75,14 @@ class Fingerprint(GenericFingerprint):
             ("1.5", ("NULLIF(%d,%d) IS NULL", "EXISTS(SELECT CURRENT_TRANSACTION FROM RDB$DATABASE)")),
             ("2.0", ("EXISTS(SELECT CURRENT_TIME(0) FROM RDB$DATABASE)", "BIT_LENGTH(%d)>0", "CHAR_LENGTH(%d)>0")),
             ("2.1", ("BIN_XOR(%d,%d)=0", "PI()>0.%d", "RAND()<1.%d", "FLOOR(1.%d)>=0")),
-            # TODO: add test for Firebird 2.5
+            ("2.5", ("'%s' SIMILAR TO '%s'",)),  # Reference: https://firebirdsql.org/refdocs/langrefupd25-similar-to.html
+            ("3.0", ("FALSE IS FALSE",)),  # https://www.firebirdsql.org/file/community/conference-2014/pdf/02_fb.2014.whatsnew.30.en.pdf
         )
 
         for i in xrange(len(table)):
             version, checks = table[i]
             failed = False
-            check = checks[randomRange(0, len(checks) - 1)].replace("%d", getUnicode(randomRange(1, 100)))
+            check = checks[randomRange(0, len(checks) - 1)].replace("%d", getUnicode(randomRange(1, 100))).replace("%s", getUnicode(randomStr()))
             result = inject.checkBooleanExpression(check)
 
             if result: