Only look for one single version of Lua: the one pointed to by the
pkgconfig package 'lua'. The wrapper set up by lua eclasses will take care
of the rest.

--- a/configure.ac
+++ b/configure.ac
@@ -1676,37 +1676,10 @@
     [disable LUA scripting support (default enabled)])])
 if test "${enable_lua}" != "no"
 then
-  PKG_CHECK_MODULES(LUA, lua5.2,
+  PKG_CHECK_MODULES(LUA, lua,
     [ have_lua=yes ],
-    [
-    AC_MSG_WARN([${LUA_PKG_ERRORS}, trying lua 5.1 instead])
-
-    PKG_CHECK_MODULES(LUA, lua5.1,
-      [ have_lua=yes ],
-      [
-      AC_MSG_WARN([${LUA_PKG_ERRORS}, trying lua >= 5.1 instead])
-      PKG_CHECK_MODULES(LUA, lua >= 5.1,
-        [ have_lua=yes ],
-        [
-          AC_MSG_WARN([${LUA_PKG_ERRORS}, trying manual detection instead])
-          have_lua=yes
-          AC_CHECK_HEADERS([lua.h lauxlib.h lualib.h],
-            [],
-            [ have_lua=no ] )
-          AC_CHECK_LIB(  lua5.2 , luaL_newstate,
-            [LUA_LIBS="-llua5.2"],
-          AC_CHECK_LIB( lua5.1 , luaL_newstate,
-            [LUA_LIBS="-llua5.1"],
-            AC_CHECK_LIB( lua51 , luaL_newstate,
-              [LUA_LIBS="-llua51"],
-              AC_CHECK_LIB( lua , luaL_newstate,
-                [LUA_LIBS="-llua"],
-                [ have_lua=no
-                ], [-lm])
-            )))
-        ])
-      ])
-    ])
+    [ have_lua=no ]
+    )
   if test "x${have_lua}" != "xyes" ;  then
       AC_MSG_ERROR([Could not find lua. Lua is needed for some interfaces (rc, telnet, http) as well as many other custom scripts. Use --disable-lua to ignore this error.])
   fi