diff --git a/lib/liquid.rb b/lib/liquid.rb
index 3be44ab..3a30a69 100644
--- a/lib/liquid.rb
+++ b/lib/liquid.rb
@@ -32,17 +32,17 @@ module Liquid
   VariableEnd                 = /\}\}/
   VariableIncompleteEnd       = /\}\}?/
   QuotedString                = /"[^"]*"|'[^']*'/
-  QuotedFragment              = /#{QuotedString}|(?:[^\s,\|'"]|#{QuotedString})+/
+  QuotedFragment              = /#{QuotedString}|(?:[^\s,\|'"]|#{QuotedString})+/o
   StrictQuotedFragment        = /"[^"]+"|'[^']+'|[^\s|:,]+/
-  FirstFilterArgument         = /#{FilterArgumentSeparator}(?:#{StrictQuotedFragment})/
-  OtherFilterArgument         = /#{ArgumentSeparator}(?:#{StrictQuotedFragment})/
-  SpacelessFilter             = /^(?:'[^']+'|"[^"]+"|[^'"])*#{FilterSeparator}(?:#{StrictQuotedFragment})(?:#{FirstFilterArgument}(?:#{OtherFilterArgument})*)?/
-  Expression                  = /(?:#{QuotedFragment}(?:#{SpacelessFilter})*)/
-  TagAttributes               = /(\w+)\s*\:\s*(#{QuotedFragment})/
+  FirstFilterArgument         = /#{FilterArgumentSeparator}(?:#{StrictQuotedFragment})/o
+  OtherFilterArgument         = /#{ArgumentSeparator}(?:#{StrictQuotedFragment})/o
+  SpacelessFilter             = /^(?:'[^']+'|"[^"]+"|[^'"])*#{FilterSeparator}(?:#{StrictQuotedFragment})(?:#{FirstFilterArgument}(?:#{OtherFilterArgument})*)?/o
+  Expression                  = /(?:#{QuotedFragment}(?:#{SpacelessFilter})*)/o
+  TagAttributes               = /(\w+)\s*\:\s*(#{QuotedFragment})/o
   AnyStartingTag              = /\{\{|\{\%/
-  PartialTemplateParser       = /#{TagStart}.*?#{TagEnd}|#{VariableStart}.*?#{VariableIncompleteEnd}/
-  TemplateParser              = /(#{PartialTemplateParser}|#{AnyStartingTag})/
-  VariableParser              = /\[[^\]]+\]|#{VariableSegment}+\??/
+  PartialTemplateParser       = /#{TagStart}.*?#{TagEnd}|#{VariableStart}.*?#{VariableIncompleteEnd}/o
+  TemplateParser              = /(#{PartialTemplateParser}|#{AnyStartingTag})/o
+  VariableParser              = /\[[^\]]+\]|#{VariableSegment}+\??/o
 end
 
 require 'liquid/drop'
diff --git a/lib/liquid/block.rb b/lib/liquid/block.rb
index c96b94c..a98874f 100644
--- a/lib/liquid/block.rb
+++ b/lib/liquid/block.rb
@@ -1,10 +1,10 @@
 module Liquid
 
   class Block < Tag
-    IsTag             = /^#{TagStart}/
-    IsVariable        = /^#{VariableStart}/
-    FullToken         = /^#{TagStart}\s*(\w+)\s*(.*)?#{TagEnd}$/
-    ContentOfVariable = /^#{VariableStart}(.*)#{VariableEnd}$/
+    IsTag             = /^#{TagStart}/o
+    IsVariable        = /^#{VariableStart}/o
+    FullToken         = /^#{TagStart}\s*(\w+)\s*(.*)?#{TagEnd}$/o
+    ContentOfVariable = /^#{VariableStart}(.*)#{VariableEnd}$/o
 
     def parse(tokens)
       @nodelist ||= []
diff --git a/lib/liquid/htmltags.rb b/lib/liquid/htmltags.rb
index dfb8c76..16efb71 100644
--- a/lib/liquid/htmltags.rb
+++ b/lib/liquid/htmltags.rb
@@ -1,6 +1,6 @@
 module Liquid
   class TableRow < Block
-    Syntax = /(\w+)\s+in\s+(#{QuotedFragment}+)/
+    Syntax = /(\w+)\s+in\s+(#{QuotedFragment}+)/o
 
     def initialize(tag_name, markup, tokens)
       if markup =~ Syntax
diff --git a/lib/liquid/tags/assign.rb b/lib/liquid/tags/assign.rb
index 1ce66b4..3540b76 100644
--- a/lib/liquid/tags/assign.rb
+++ b/lib/liquid/tags/assign.rb
@@ -9,7 +9,7 @@ module Liquid
   #  {{ foo }}
   #
   class Assign < Tag
-    Syntax = /(#{VariableSignature}+)\s*=\s*(.*)\s*/   
+    Syntax = /(#{VariableSignature}+)\s*=\s*(.*)\s*/o
   
     def initialize(tag_name, markup, tokens)          
       if markup =~ Syntax
diff --git a/lib/liquid/tags/case.rb b/lib/liquid/tags/case.rb
index 9597059..4e2fb2c 100644
--- a/lib/liquid/tags/case.rb
+++ b/lib/liquid/tags/case.rb
@@ -1,7 +1,7 @@
 module Liquid
   class Case < Block
-    Syntax     = /(#{QuotedFragment})/
-    WhenSyntax = /(#{QuotedFragment})(?:(?:\s+or\s+|\s*\,\s*)(#{QuotedFragment}.*))?/
+    Syntax     = /(#{QuotedFragment})/o
+    WhenSyntax = /(#{QuotedFragment})(?:(?:\s+or\s+|\s*\,\s*)(#{QuotedFragment}.*))?/o
 
     def initialize(tag_name, markup, tokens)      
       @blocks = []
diff --git a/lib/liquid/tags/cycle.rb b/lib/liquid/tags/cycle.rb
index 1df692e..9b3f342 100644
--- a/lib/liquid/tags/cycle.rb
+++ b/lib/liquid/tags/cycle.rb
@@ -13,8 +13,8 @@ module Liquid
   #    <div class="green"> Item five</div>
   #
   class Cycle < Tag
-    SimpleSyntax = /^#{QuotedFragment}+/        
-    NamedSyntax  = /^(#{QuotedFragment})\s*\:\s*(.*)/
+    SimpleSyntax = /^#{QuotedFragment}+/o
+    NamedSyntax  = /^(#{QuotedFragment})\s*\:\s*(.*)/o
   
     def initialize(tag_name, markup, tokens)      
       case markup
@@ -48,7 +48,7 @@ module Liquid
   
     def variables_from_string(markup)
       markup.split(',').collect do |var|
-    	  var =~ /\s*(#{QuotedFragment})\s*/
+    	  var =~ /\s*(#{QuotedFragment})\s*/o
     	  $1 ? $1 : nil
     	end.compact
     end
@@ -56,4 +56,4 @@ module Liquid
   end
   
   Template.register_tag('cycle', Cycle)
-end
\ No newline at end of file
+end
diff --git a/lib/liquid/tags/for.rb b/lib/liquid/tags/for.rb
index a2ece81..247f095 100644
--- a/lib/liquid/tags/for.rb
+++ b/lib/liquid/tags/for.rb
@@ -44,7 +44,7 @@ module Liquid
   # forloop.last:: Returns true if the item is the last item.
   #
   class For < Block                                             
-    Syntax = /(\w+)\s+in\s+(#{QuotedFragment}+)\s*(reversed)?/   
+    Syntax = /(\w+)\s+in\s+(#{QuotedFragment}+)\s*(reversed)?/o
   
     def initialize(tag_name, markup, tokens)
       if markup =~ Syntax
diff --git a/lib/liquid/tags/if.rb b/lib/liquid/tags/if.rb
index 3b77732..7f23dde 100644
--- a/lib/liquid/tags/if.rb
+++ b/lib/liquid/tags/if.rb
@@ -13,8 +13,8 @@ module Liquid
   #
   class If < Block
     SyntaxHelp = "Syntax Error in tag 'if' - Valid syntax: if [expression]"
-    Syntax = /(#{QuotedFragment})\s*([=!<>a-z_]+)?\s*(#{QuotedFragment})?/
-    ExpressionsAndOperators = /(?:\b(?:\s?and\s?|\s?or\s?)\b|(?:\s*(?!\b(?:\s?and\s?|\s?or\s?)\b)(?:#{QuotedFragment}|\S+)\s*)+)/
+    Syntax = /(#{QuotedFragment})\s*([=!<>a-z_]+)?\s*(#{QuotedFragment})?/o
+    ExpressionsAndOperators = /(?:\b(?:\s?and\s?|\s?or\s?)\b|(?:\s*(?!\b(?:\s?and\s?|\s?or\s?)\b)(?:#{QuotedFragment}|\S+)\s*)+)/o
 
     def initialize(tag_name, markup, tokens)
       @blocks = []
diff --git a/lib/liquid/tags/include.rb b/lib/liquid/tags/include.rb
index 9ea7323..f7400ab 100644
--- a/lib/liquid/tags/include.rb
+++ b/lib/liquid/tags/include.rb
@@ -1,6 +1,6 @@
 module Liquid
   class Include < Tag
-    Syntax = /(#{QuotedFragment}+)(\s+(?:with|for)\s+(#{QuotedFragment}+))?/
+    Syntax = /(#{QuotedFragment}+)(\s+(?:with|for)\s+(#{QuotedFragment}+))?/o
   
     def initialize(tag_name, markup, tokens)      
       if markup =~ Syntax
@@ -62,4 +62,4 @@ module Liquid
   end
 
   Template.register_tag('include', Include)  
-end
\ No newline at end of file
+end
diff --git a/lib/liquid/variable.rb b/lib/liquid/variable.rb
index cb0b612..837c588 100644
--- a/lib/liquid/variable.rb
+++ b/lib/liquid/variable.rb
@@ -11,7 +11,7 @@ module Liquid
   #   {{ user | link }}
   #
   class Variable
-    FilterParser = /(?:#{FilterSeparator}|(?:\s*(?!(?:#{FilterSeparator}))(?:#{QuotedFragment}|\S+)\s*)+)/
+    FilterParser = /(?:#{FilterSeparator}|(?:\s*(?!(?:#{FilterSeparator}))(?:#{QuotedFragment}|\S+)\s*)+)/o
     attr_accessor :filters, :name
 
     def initialize(markup)