diff --git a/mode/tt.py b/mode/tt.py
index e011103..e6f9fee 100644
--- a/mode/tt.py
+++ b/mode/tt.py
@@ -4,7 +4,7 @@ import mode.xml
 import mode.html
 import mode.javascript
 import mode.css
-from mode.perl import StringGrammar, PerlGrammar
+from mode.perl import StrictStringGrammar, StringGrammar, PerlGrammar
 
 class PerlDirectiveGrammar(Grammar):
     rules = [PatternRule('tt.perl', '(?:PERL|RAWPERL|END)(?![A-Z_])')]
@@ -14,7 +14,7 @@ class DirectiveGrammar(Grammar):
         PatternRule('tt.keyword', r'(?:BLOCK|CALL|CASE|CATCH|CLEAR|DEBUG|DEFAULT|FINAL|FILTER|FOREACH|ELSIF|ELSE|END|GET|IF|INCLUDE|INSERT|IN|LAST|MACRO|META|NEXT|PERL|PROCESS|RAWPERL|RETURN|SET|STOP|SWITCH|TAGS|THROW|TRY|UNLESS|USE|WHILE|WRAPPER)(?![A-Z_])'),
         PatternRule('attribute', '[a-zA-Z_][a-zA-Z0-9_]*(?= *=)'),
         RegionRule('string', '"', StringGrammar, '"'),
-        RegionRule('string', "'", StringGrammar, "'"),
+        RegionRule('string', "'", StrictStringGrammar, "'"),
     ]
 
 crule = RegionRule('comment', r'\[\%#', Grammar, r'%%\]')