lib/kramdown/parser/kramdown/header.rb in kramdown-1.1.0 vs lib/kramdown/parser/kramdown/header.rb in kramdown-1.2.0

@@ -11,10 +11,10 @@
 
 module Kramdown
   module Parser
     class Kramdown
 
-      HEADER_ID=/(?:[ \t]+\{#(\w[\w-]*)\})?/
+      HEADER_ID=/(?:[ \t]+\{#([A-Za-z][\w:-]*)\})?/
       SETEXT_HEADER_START = /^(#{OPT_SPACE}[^ \t].*?)#{HEADER_ID}[ \t]*?\n(-|=)+\s*?\n/
 
       # Parse the Setext header at the current location.
       def parse_setext_header
         return false if !after_block_boundary?