card->hbnr.init = NUM_HB;
        card->hbnr.max = MAX_HB;
 
-       card->sm_handle = 0x00000000;
+       card->sm_handle = NULL;
        card->sm_addr = 0x00000000;
-       card->lg_handle = 0x00000000;
+       card->lg_handle = NULL;
        card->lg_addr = 0x00000000;
 
        card->efbie = 1;        /* To prevent push_rxbufs from enabling the interrupt */
                                addr2 = card->sm_addr;
                                handle2 = card->sm_handle;
                                card->sm_addr = 0x00000000;
-                               card->sm_handle = 0x00000000;
+                               card->sm_handle = NULL;
                        } else {        /* (!sm_addr) */
 
                                card->sm_addr = addr1;
                                addr2 = card->lg_addr;
                                handle2 = card->lg_handle;
                                card->lg_addr = 0x00000000;
-                               card->lg_handle = 0x00000000;
+                               card->lg_handle = NULL;
                        } else {        /* (!lg_addr) */
 
                                card->lg_addr = addr1;