diff --git a/ChangeLog b/ChangeLog
index 66be43b91..2e374a408 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,13 @@
+2010-09-30  Robert Larice
+ * src/xspice/cmpp/Makefile.am ,
+ * src/xspice/cmpp/ifs_lex.l ,
+ * src/xspice/cmpp/mod_lex.l :
+    always use flex instead of an arbitrary lex,
+    use flex specific %options, to clean up the Makefile
+    don't write the lexer via stdout, to improve gcc warning readability
+    this works around a bug as well, which caused erronous lexer c files
+    to be included in the distribution tar ball
+
 ============================ Rework-22 ==================================
 2010-09-26  Holger Vogt
  * .cvsignore: m4 entry removed
diff --git a/src/xspice/cmpp/Makefile.am b/src/xspice/cmpp/Makefile.am
index b1feb94e5..7d087462e 100644
--- a/src/xspice/cmpp/Makefile.am
+++ b/src/xspice/cmpp/Makefile.am
@@ -6,7 +6,7 @@ EXTRA_DIST = ifs_lex.l mod_lex.l ifs_yacc.h mod_yacc.h
 
 MAINTAINERCLEANFILES = Makefile.in
 
-LEX = @LEX@ -t
+LEX = flex
 BISON = bison
 
 bin_PROGRAMS = cmpp
@@ -17,11 +17,11 @@ cmpp_SOURCES = cmpp.h main.c pp_ifs.c pp_lst.c pp_mod.c read_ifs.c util.c \
 
 mod_lex.o : mod_yacc.h
 mod_lex.c : mod_lex.l
-	$(LEX)  -Pmod_yy $< > $@
+	$(LEX)  -o $@  $<
 
 ifs_lex.o : ifs_yacc.h
 ifs_lex.c : ifs_lex.l
-	$(LEX)  -i -Pifs_yy $< > $@
+	$(LEX)  -o $@  $<
 
 ifs_yacc.c ifs_yacc.h : ifs_yacc.y
 	$(BISON) $(BISONFLAGS) -d -o ifs_yacc.c $<
diff --git a/src/xspice/cmpp/ifs_lex.l b/src/xspice/cmpp/ifs_lex.l
index 9a52a146b..a2e2c5252 100755
--- a/src/xspice/cmpp/ifs_lex.l
+++ b/src/xspice/cmpp/ifs_lex.l
@@ -1,3 +1,5 @@
+%option case-insensitive
+%option prefix="ifs_yy"
 %option yylineno
 %option noyywrap
 %{ /* $Id$ */
diff --git a/src/xspice/cmpp/mod_lex.l b/src/xspice/cmpp/mod_lex.l
index 40c8cf049..712d9a961 100755
--- a/src/xspice/cmpp/mod_lex.l
+++ b/src/xspice/cmpp/mod_lex.l
@@ -1,3 +1,4 @@
+%option prefix="mod_yy"
 %option yylineno
 %option noyywrap
 %{ /* $Id$ */