diff --git a/iolib.c b/iolib.c
index 8a531e50..3a532c8a 100644
--- a/iolib.c
+++ b/iolib.c
@@ -302,5 +302,6 @@ void iolib_open (void)
   lua_tagio = lua_newtag();
   lua_infile=stdin; lua_outfile=stdout;
   luaL_openlib(iolib, (sizeof(iolib)/sizeof(iolib[0])));
-  lua_seterrormethod(errorfb);
+  lua_pushcfunction(errorfb);
+  lua_seterrormethod();
 }
diff --git a/lua.h b/lua.h
index 9b1e8dce..cc5ed897 100644
--- a/lua.h
+++ b/lua.h
@@ -2,7 +2,7 @@
 ** LUA - An Extensible Extension Language
 ** TeCGraf: Grupo de Tecnologia em Computacao Grafica, PUC-Rio, Brazil
 ** e-mail: lua@tecgraf.puc-rio.br
-** $Id: lua.h,v 4.8 1997/06/16 19:48:18 roberto Exp roberto $
+** $Id: lua.h,v 4.9 1997/06/18 21:20:45 roberto Exp roberto $
 */
 
 
@@ -21,9 +21,9 @@
 typedef void (*lua_CFunction) (void);
 typedef unsigned int lua_Object;
 
-lua_Object     lua_settagmethod	(int tag, char *event, lua_CFunction method);
+lua_Object     lua_settagmethod	(int tag, char *event);  /* In: new method */
 lua_Object     lua_gettagmethod	(int tag, char *event);
-lua_Object     lua_seterrormethod (lua_CFunction method);
+lua_Object     lua_seterrormethod (void);  /* In: new method */
 
 int            lua_newtag		(void);
 void           lua_settag		(int tag); /* In: object */
diff --git a/manual.tex b/manual.tex
index 6e6d524e..2d19ac88 100644
--- a/manual.tex
+++ b/manual.tex
@@ -1,4 +1,4 @@
-% $Id: manual.tex,v 2.1 1997/06/18 20:14:52 roberto Exp roberto $
+% $Id: manual.tex,v 2.2 1997/06/18 21:11:53 roberto Exp roberto $
 
 \documentstyle[fullpage,11pt,bnf]{article}
 
@@ -38,7 +38,7 @@ Waldemar Celes
 \tecgraf\ --- Computer Science Department --- PUC-Rio
 }
 
-\date{\small \verb$Date: 1997/06/18 20:14:52 $}
+\date{\small \verb$Date: 1997/06/18 21:11:53 $}
 
 \maketitle
 
@@ -1457,19 +1457,20 @@ Otherwise, the whole program terminates with a call to \verb|exit(1)|.
 The error handler method \see{error} can be changed with:
 \Deffunc{lua_seterrormethod}
 \begin{verbatim}
-lua_Object     lua_seterrormethod (lua_CFunction method);
+lua_Object     lua_seterrormethod (void);
 \end{verbatim}
-This function returns a \verb|lua_Object|,
-which is the old error method value.
+This function sets the object at the top of C2lua
+as the new error method,
+and returns the old error method value.
 
 Tag methods can be changed with:
 \Deffunc{lua_settagmethod}
 \begin{verbatim}
-lua_Object     lua_settagmethod (int tag, char *event, lua_CFunction method);
+lua_Object     lua_settagmethod (int tag, char *event);
 \end{verbatim}
 The first parameter is the tag,
-the second is the event name \see{tag-method},
-and the third is a CFunction to be used as the new method.
+the second is the event name \see{tag-method};
+the new method is pushed from C2lua.
 This function returns a \verb|lua_Object|,
 which is the old tag method value.
 To get just the current value of a tag method,
diff --git a/mathlib.c b/mathlib.c
index 17e301da..bb33db08 100644
--- a/mathlib.c
+++ b/mathlib.c
@@ -3,7 +3,7 @@
 ** Mathematics library to LUA
 */
 
-char *rcs_mathlib="$Id: mathlib.c,v 1.23 1997/04/06 14:08:08 roberto Exp roberto $";
+char *rcs_mathlib="$Id: mathlib.c,v 1.24 1997/06/09 17:30:10 roberto Exp roberto $";
 
 #include <stdlib.h>
 #include <math.h>
@@ -210,7 +210,8 @@ static struct luaL_reg mathlib[] = {
 void mathlib_open (void)
 {
   luaL_openlib(mathlib, (sizeof(mathlib)/sizeof(mathlib[0])));
+  lua_pushcfunction(math_pow);
   lua_pushnumber(0);  /* to get its tag */
-  lua_settagmethod(lua_tag(lua_pop()), "pow", math_pow);
+  lua_settagmethod(lua_tag(lua_pop()), "pow");
 }
 
diff --git a/opcode.c b/opcode.c
index d373dcec..982b1da9 100644
--- a/opcode.c
+++ b/opcode.c
@@ -3,7 +3,7 @@
 ** TecCGraf - PUC-Rio
 */
 
-char *rcs_opcode="$Id: opcode.c,v 4.11 1997/06/16 19:48:18 roberto Exp roberto $";
+char *rcs_opcode="$Id: opcode.c,v 4.12 1997/06/19 17:46:12 roberto Exp roberto $";
 
 #include <setjmp.h>
 #include <stdio.h>
@@ -654,21 +654,21 @@ lua_Object lua_gettagmethod (int tag, char *event)
   return put_luaObjectonTop();
 }
 
-lua_Object lua_settagmethod (int tag, char *event, lua_CFunction method)
+lua_Object lua_settagmethod (int tag, char *event)
 {
+  TObject newmethod;
+  checkCparams(1);
+  newmethod = *(--top);
   lua_pushnumber(tag);
   lua_pushstring(event);
-  if (method)
-    lua_pushcfunction (method);
-  else
-    lua_pushnil();
+  *top = newmethod;  incr_top;
   do_unprotectedrun(luaI_settagmethod, 3, 1);
   return put_luaObjectonTop();
 }
 
-lua_Object lua_seterrormethod (lua_CFunction method)
+lua_Object lua_seterrormethod (void)
 {
-  lua_pushcfunction(method);
+  checkCparams(1);
   do_unprotectedrun(luaI_seterrormethod, 1, 1);
   return put_luaObjectonTop();
 }