--- flex-2.5.31/flex.skl	2003-04-01 04:51:38.000000000 +0300
+++ flex/flex.skl	2003-10-24 21:47:10.000000000 +0300
@@ -27,6 +27,11 @@
 %# Macros for runtime processing stage.
 m4_changecom
 m4_changequote
+
+%# Let user use our quoting strings
+m4_changequote({, })
+m4_define( {m4_userquote_start}, {m4_changequote(<, >)[[m4_changequote([[, ]])})
+m4_define( {m4_userquote_end}, {m4_changequote(<, >)]]m4_changequote([[, ]])})
 m4_changequote([[, ]])
 
 %# 
--- flex-2.5.31/scan.l	2003-04-01 04:51:38.000000000 +0300
+++ flex/scan.l	2003-10-24 21:51:20.000000000 +0300
@@ -194,8 +194,14 @@
 <COMMENT>{
 	"*/"		ACTION_ECHO; yy_pop_state();
 	"*"		ACTION_ECHO;
-	[^*\n]+		ACTION_ECHO;
-	[^*\n]*{NL}	++linenum; ACTION_ECHO;
+	[\[\]]		ACTION_ECHO;
+	[^*\[\]\n]+	ACTION_ECHO;
+	[^*\[\]\n]*{NL}	++linenum; ACTION_ECHO;
+	\[\[		add_action("[" "[]" "]m4_" "userquote_start()");
+	\]\]		add_action("[" "[]" "]m4_" "userquote_end()");
+			/* Macros need to be clearly separated from surrounding
+			 * text and this file needs to go through flex untouched.
+			 */
 }
 
 <LINEDIR>{