you can use format like '<90>foo</90>'.

lib/termcolor.rb

@@ -36,9 +36,11 @@ def initialize
     end
 
     def tag_start(name, attrs)
-      @result << HighLine.const_get(name.upcase)
-      @tag_stack.push(name)
-    rescue NameError
+      esc_seq = to_esc_seq(name)
+      if esc_seq
+        @result << esc_seq
+        @tag_stack.push(name)
+      end
     end
 
     def text(text)
@@ -48,8 +50,19 @@ def text(text)
     def tag_end(name)
       @tag_stack.pop
       @result << HighLine::CLEAR
-      @result << HighLine.const_get(@tag_stack[-1].upcase) unless @tag_stack.empty?
+      @result << to_esc_seq(@tag_stack[-1].upcase) unless @tag_stack.empty?
     end
 
+    def to_esc_seq(name)
+      esc_seq = nil
+      begin
+        esc_seq = HighLine.const_get(name.upcase)
+      rescue NameError
+        if name =~ /^\d+$/
+          esc_seq = "\e[#{name}m"
+        end
+      end
+      esc_seq
+    end
   end
 end

spec/termcolor_spec.rb

@@ -24,6 +24,12 @@ module TermColor
       text.should == "aa\e[34maaaaa<aaa\"aaa>aaa&aaaaa\e[0maaa"
     end
 
+    it 'should parse 3' do
+      text = TermColor.parse('aa<30>bbbbbbb<32>cccc<90>ddd</90>c</32>b</30>aaa')
+      puts text
+      text.should == "aa\e[30mbbbbbbb\e[32mcccc\e[90mddd\e[0m\e[32mc\e[0m\e[30mb\e[0maaa"
+    end
+
     it 'should raise Error' do
       lambda{ TermColor.parse('aaaaa<red>aaaaa</blue>aaaaa') }.should raise_error(TermColor::ParseError)
       lambda{ TermColor.parse('aaaaa<red>aaaaaaaaaa') }.should_not raise_error(TermColor::ParseError)
@@ -33,5 +39,15 @@ module TermColor
       text = 'a<foo>&</foo>a'
       TermColor.escape(text).should == "a&lt;foo&gt;&amp;&lt;/foo&gt;a"
     end
+
+    it 'should convert to escape sequence' do
+      listener = TermColor::MyListener.new
+      listener.to_esc_seq('red').should == "\e[31m"
+      listener.to_esc_seq('on_red').should == "\e[41m"
+      listener.to_esc_seq('foo').should == nil
+      listener.to_esc_seq('0').should == "\e[0m"
+      listener.to_esc_seq('31').should == "\e[31m"
+      listener.to_esc_seq('031').should == "\e[031m"
+    end
   end
 end