diff --git a/cpu/ppc4xx/4xx_enet.c b/cpu/ppc4xx/4xx_enet.c
index 81d49ff..aefe126 100644
--- a/cpu/ppc4xx/4xx_enet.c
+++ b/cpu/ppc4xx/4xx_enet.c
@@ -264,10 +264,10 @@
 		bis->bi_phymode[3] = BI_PHYMODE_ZMII;
 		break;
 	case 2:
-		zmiifer = ZMII_FER_SMII << ZMII_FER_V(0);
-		zmiifer = ZMII_FER_SMII << ZMII_FER_V(1);
-		zmiifer = ZMII_FER_SMII << ZMII_FER_V(2);
-		zmiifer = ZMII_FER_SMII << ZMII_FER_V(3);
+		zmiifer |= ZMII_FER_SMII << ZMII_FER_V(0);
+		zmiifer |= ZMII_FER_SMII << ZMII_FER_V(1);
+		zmiifer |= ZMII_FER_SMII << ZMII_FER_V(2);
+		zmiifer |= ZMII_FER_SMII << ZMII_FER_V(3);
 		bis->bi_phymode[0] = BI_PHYMODE_ZMII;
 		bis->bi_phymode[1] = BI_PHYMODE_ZMII;
 		bis->bi_phymode[2] = BI_PHYMODE_ZMII;