diff --git a/tc/tc_core.c b/tc/tc_core.c
index b5e362f..9ae4d8e 100644
--- a/tc/tc_core.c
+++ b/tc/tc_core.c
@@ -84,11 +84,12 @@
 			cell_log++;
 	}
 	for (i=0; i<256; i++) {
-		unsigned sz = (i<<cell_log);
+		unsigned sz = ((i+1)<<cell_log);
 		if (sz < mpu)
 			sz = mpu;
 		rtab[i] = tc_calc_xmittime(bps, sz);
 	}
+	r->cell_align=-1; // Due to the sz calc
 	r->cell_log=cell_log;
 	return cell_log;
 }