diff --git a/lua/zapret-lib.lua b/lua/zapret-lib.lua
index de05616..edccb56 100644
--- a/lua/zapret-lib.lua
+++ b/lua/zapret-lib.lua
@@ -153,7 +153,7 @@ function apply_arg_prefix(desync)
 		local c = string.sub(v,1,1)
 		if c=='#' then
 			local blb = blob(desync,string.sub(v,2))
-			desync.arg[a] = (type(blb)=='string' or type(blb)=='table') and #blb or 0
+			desync.arg[a] = tostring((type(blb)=='string' or type(blb)=='table') and #blb or 0)
 		elseif c=='%' then
 			desync.arg[a] = blob(desync,string.sub(v,2))
 		elseif c=='\\' then
@@ -545,6 +545,7 @@ function blob(desync, name, def)
 				error("blob  '"..name.."' unavailable")
 			end
 		end
+		blob = tostring(blob)
 	end
 	return blob
 end
diff --git a/nfq2/lua.c b/nfq2/lua.c
index fcb5559..a783bce 100644
--- a/nfq2/lua.c
+++ b/nfq2/lua.c
@@ -1248,6 +1248,7 @@ void lua_push_blob(lua_State *L, int idx_desync, const char *blob)
 		lua_pop(L,1);
 		lua_getglobal(L, blob);
 	}
+	lua_tostring(L,-1);
 }
 void lua_pushf_blob(lua_State *L, int idx_desync, const char *field, const char *blob)
 {
@@ -1779,7 +1780,10 @@ void lua_pushf_args(lua_State *L, const struct str2_list_head *args, int idx_des
 				lua_push_blob(L, idx_desync, val+1);
 				lua_Integer len = lua_rawlen(L, -1);
 				lua_pop(L,1);
-				lua_pushf_int(L, var, len);
+				lua_pushstring(L, var);
+				lua_pushinteger(L, len);
+				lua_tostring(L,-1); // force string type in arg
+				lua_rawset(L,-3);
 			}
 			else
 				lua_pushf_str(L, var, val);